It was a mark as to how badly affected Y/N was that he didn't feel the cloak until it was almost on top of them.

'Come on,' said Harry's voice, 'we need to go.'

'Hagrid needs us,' said Y/N.

'I know-' began Harry.

'No!' hissed Ron at once. 'We'll get Hagrid in more trouble, we need to get back up to the castle.'

'We can't just leave him! We need-!' began Y/N and suddenly Ron materialised in front of him. He was looking in Y/N's general direction, so Y/N held his gaze. Scabbers was still fighting his grip, but Ron was doing a good job of holding him.

'We need to go,' said Ron flatly. 'I want to go down there as much as you do, but Fudge, Dumbledore, and the executioner are all down there. We'll all get expelled. They still think Black's after Harry and we've got Scabbers now. We need answers.'

Y/N opened his mouth to respond but there was a look on Ron's face, one he hadn't seen there before, that made him falter.

'Yeah, okay,' said Y/N. 'Let's-'

'Crookshanks, no!' hissed Hermione.

Y/N span around to see Crookshanks sunk low to the ground, creeping steadily towards him.

'Sorry Mione,' he said as his wand shot out of the holster. 'Impedimenta!'

Crookshanks froze in his tracks.

'Let's go quick, before Black-' but even as he was saying it, Y/N could feel it was too late. His gaze travelled back towards Hagrid's hut and saw the massive black dog barrelling towards them.

Of course, it knew Crookshanks. It made sense it was also working with Black, especially with how smart it was. Y/N pushed past his friends and removed his own disillusionment charm.

The dog slid to a halt a distance away from them, its eyes on Y/N.

'Tell Black we've got Scabbers, we'll get our own answers and report to him if we need to.'

The dog stood stock still for a few seconds. Y/N could have sworn he saw a look of apology cross the features before it lunged. Both paws went into Y/N's chest and he was sent crashing to the ground. The dog used him as a platform to leap off and continued its sprint towards Ron.

The dog sank its teeth around Ron's arm and began dragging him away. Y/N rolled onto his front and pushed himself up searching for his wand. Unfortunately, the dog disarming him had brought enough time for Crookshanks to get free. A split-second later and he saw the ginger flash running past with a very familiar looking stick of wood in his mouth.

'Blasted smart cat,' he snarled as he got to his feet. He went to give chase, but his heart sank as he heard a shriek of pain and span around. Both Harry and Hermione were on the floor. They had given chase to the dog which was dragging Ron towards the Whomping Willow and the flailing branches had hit both of them to the ground.

Y/N sprinted forward just as the tree reared back. He shoved himself between the swinging branch and Hermione just as it connected. He felt the harsh wood lash across his back and could have sworn he felt his shirt rip.

He grabbed her under the arms and scooped her onto her feet just as Harry scrambled to his own and they moved out the way of the flailing branches.

'Lumos!' said Harry, the end of his wand ignited and revealed the trunk where there seemed to be an opening. The torso of Ron was just disappearing through it. Y/N watched him wrap his foot around one of the roots in an attempt to prevent the dog dragging him away.

'We have to get him,' said Harry.

'Through all of this?' squealed Hermione as another branch whipped across dangerously close to them. They were out of reach, but barely.

'We can't exactly-' but Y/N was cut off as a sickening crack rang across the grounds. Y/N felt his blood begin to boil.

'We've got to go for help!' yelled Hermione, but Y/N was looking around. Then he spotted it, on the ground a few feet away. His wand.

He scooped it up not even bothering to check for where Crookshanks was and yelled, 'Impedimenta!' the branch swinging across in front of them slowed and he charged forward-

-only to get hit by another one that came swinging in from the side. It caught him hard around the waist and he was sent crashing to floor. He heard a scream from behind him but did not care. He felt betrayed by the dog, by Crookshanks. He would not leave Ron to Black alone. He staggered to his feet just as he heard the creaking of the tree pulling back and raised his wand.

'Protego!'

It barely did anything to soften the blow. This time it lashed across his face and as it smacked his face to the side. He watched a spurt of blood follow and splatter across the grass.

Another caught him hard in the stomach and he was sent spiralling onto the ground again. His vision blurred slightly, but he watched as the tree reeled back with a branch the width of a tire.

And then it stopped.

A split second later and he was enveloped in brown.

'What on earth were you thinking?' shrieked Hermione as she inspected the wound on his face. 'You could have been killed!'

'I was hardly going to leave him to Black, was I?' said Y/N, wincing slightly as Hermione ran a finger along the cut on his face. 'Besides, I'm fine aren't I?'

'Only because of Crookshanks,' said Harry. 'Lucky him and that dog know each other. Crookshanks knows how to stop the Willow.'

'And I reckon they both know Black,' said Y/N, staring towards the entrance that Ron had been dragged through. 'We have to go after him.'

'You can't!' said Hermione at once. 'You're injured-!'

'Hermione, Ron's ankle just broke. We all heard it, we need to get in there. Who knows what'll happen in the time it takes to get anyone down here.'

Hermione did not look impressed, but she gave a sigh and nodded.

'Fine, but you're doing everything I say and nothing reckless whilst we're down there. Understand?'

'Don't think this is the time for that, 'Mione-'

'Do. You. Understand?' the look in her face was murderous.

'Yep. Alright 'Mione, we do it your way,' said Y/N, allowing her to help him to his feet.

'Good, now stand still. Ferula.'

Y/N felt bandages spring up around his stomach and the wound across his back covering them both. The wind felt cold and harsh on the mark on his face, but there was little that could be done with that yet.

'Come on,' said Harry.

Together, the three of them moved towards the base of the tree where Y/N now saw Crookshanks with a paw pressed up against a knot on the trunk.

'Makes sense,' said Y/N. 'They'd need a way to turn it off to bring Remus in here.'

Hermione nodded, but Harry didn't seem to have been listening. He dropped to his hands and knees and crawled away into the tunnel. Hermione went next, Y/N holstered his wand before following on last.

He felt something squeezing past him as he entered and Crookshanks slunk past all of them to the front of the line and began leading the way through the tunnel.

The tunnel was large enough that they didn't need to remain on hands and knees once inside, though they did need to stoop to prevent their heads scraping the solid ground above. Y/N especially, he was bent almost double which wasn't easy with how tightly the bandages were wrapped around his back and waist.

Hermione held back and hurried alongside him, entangling her fingers with his own whilst Harry took the lead, his wand lit, following the shadow of Crookshanks.

'Pretty sure this tunnel leads to the Shrieking Shack,' said Harry's voice, loud enough to carry back to them.

'It does,' he replied. 'Remus told me about it a while back. They covered it up to help keep the school secure.'

Y/N didn't know why he felt the need to lie but he wanted to preserve Remus' secret, he didn't know how Harry would take it. He knew him and Remus were close.

It was very difficult running whilst stooped over the way he was. Luckily, he wasn't the only one being affected, before too long the heavy breathing of the three of them echoed off the walls around them.

Especially once the tunnel began to rise and twist. This, however, was where the tunnel ended. They took one last turn and a small patch of dim light filtered into the tunnel. Harry raised his still lit wand just as Hermione raised her own and said 'Lumos'. Y/N left his in his holster.

They stepped out into a very cluttered and dusty room, it looked as though half the belongings had been thrown around haphazardly, many pieces of furniture were smashed across the floor and the windows were boarded up. Large slash marks ran across several of the walls and pieces of scattered wood.

'Ghosts didn't do that,' said Harry, pointing at a chair that was missing a leg.

'No. But maybe our dog did,' said Y/N evasively.

Something creaked overhead and all three of them looked up.

'Somethings moving around up there,' said Harry.

'Reckon it's Black?' asked Y/N.

'Let's hope he's as friendly to all of us as he was to you,' said Hermione, and she turned to lead the way upstairs. Y/N followed on behind with Harry at the rear.

They were keeping as quiet as they could and it's as though the house knew it. Every step seemed to be muffled by the dust under foot. They reached the landing at the top of the staircase and saw a long drag mark clearly through the dust leading to a door.

'Nox,' whispered Harry and Hermione and both wands went out. They crept forward and Y/N pushed the door open.

The room looked like a master bedroom of some description, though currently all they could see was a magnificent four-poster bed with very dusty hangings. On which sat Crookshanks, who began purring upon their arrival, and Ron, whose leg was stuck out at an angle it shouldn't be. He was still clutching Scabbers to his chest.

Harry ran forward. Y/N and Hermione followed cautiously, both sweeping the room.

'Ron? Are you okay?' Harry was saying, but Y/N was staring at the floor. In the dust were distinct paw prints, but they seemed to turn into human footprints halfway through.

'Expelliarmus!' came a painfully familiar voice from behind Y/N.

He span around just in time to watch Hermione and Harry's wands go flying out of their hands and towards Sirius Black, who caught them and, with a foot, kicked the door shut. Y/N crossed the room in three strides and stood between Black and Hermione.

'Y/N no,' Hermione hissed, but Y/N ignored her.

'Black, we can talk about this.'

'I was hoping you'd follow,' said Black, looking between Y/N and Harry. 'You're both loyal. Just like your father,' he added with a nod to Harry. Harry's face tightened, but he didn't move.

'Did that one night in the Common Room tell you everything about me?' asked Y/N.

'No, but this morning in the grounds did. All that time and effort you put into saving Buckbeak. Hours spent in the grounds just waiting to hear about the result of his appeal.'

'How do you-?' began Y/N, but it was Ron who responded.

'He's the dog, Y/N,' he said through gritted teeth. 'He's an Animagus.'

And everything clicked into place. Him gaining trust over Crookshanks, not getting caught in the grounds, being able to sneak into the Castle, the intelligence of the dog that morning and-

'That's how you knew we had Scabbers again,' said Y/N. 'I invited you to Buckbeak's execution. You seemed genuinely interested.'

'And I was,' said Black. 'Truly was a fascinating creature. But once I heard you all leaving and could smell that rat on you, I followed. You were all invisible, so it made it difficult, but then you revealed yourselves.'

'That's why you looked apologetic when you jumped me,' said Y/N.

'I was hoping you'd stay out of the way. I didn't want to hurt you. But you gave me no choice. Now, get out of my way.'

'Or what?' asked Y/N, his eyes narrowing. 'Whether I believe you're in it to kill Harry or not doesn't matter anymore, Black. We need more of an explanation than that.'

'You can have it after I've done what I need to do.'

'Expelliarmus!' the wand shot out of Y/N's holster and into his hand. The three wands went spiralling into the air and Y/N caught them. 'I think you'll explain first.'

'We don't have time-' hissed Black.

'You seemed to have time whilst you were waiting for us to follow you through the tunnel. And we've got all night,' said Y/N.

'Get out of my way, Y/N,' said Black, but Y/N held his gaze. The two stared at each other for a solid few seconds before a voice snapped them both out of it.

'Please…'

They both turned to look at Harry. He'd strode up alongside Y/N. Y/N could see him shaking, whether it was nerves or anger he couldn't tell. 'Please, I need to know what happened to my parents. Did you betray them?'

'I got them killed,' said Black as he hung his head, 'But… if I am to give you the full story-' he was interrupted once again however as they heard footsteps running around beneath them. Y/N stomped twice on the floor to show where they were and they heard the footsteps get closer, across the room below, up the stairs, across the landing.

Then the door flew upon, and Remus came tearing into the room. His face was pale and his wand was raised. He took one look around the room and pointed his wand at Y/N.

'Expelliarmus!'

All four wands went soaring out of his hand and Remus caught them all. He gave Y/N a look and then turned towards Black.

'Where is he, Sirius?'

Black's face was quite expressionless but after a few seconds he steadily raised a hand to point at Scabbers on Ron's chest.

'But then…' said Remus, who seemed to be trying to stare into Black's soul. 'Why hasn't he shown himself before now? Unless-' Remus' eyes widened in realisation, '-unless he was the one? Unless you switched, without telling me?'

Black nodded slowly.

'Professor-?' began Harry, but words failed him as it did all of them. Remus stowed his wand away, walked over to Black and embraced him like a brother.

Y/N felt his knuckles tighten. Old friends or not, they were still face-to-face with a wanted man who had not yet explained anything.

'Remus,' said Y/N. Remus broke apart from Black and turned to look at him 'I've done everything I can for you. I have a lot of respect for you. So, before I go running up to the Castle screaming bloody murder, can you please tell us what on earth is going on and give me back my wand?'

'Happily,' said Remus in a tone as though he had simply asked a question in class. He threw all four wands back to Y/N who dished them out to his friends then turned to face Ron.

'Episkey.'

It wasn't perfect, nothing short of Madam Pomfrey was going to be, but Ron's leg was now at least at a much healthier angle and some of the colour had returned to his face.

'Thanks Y/N,' he muttered, and Y/N nodded before turning back to Remus and tucking his wand away into its holster.

'Now, we're going to start at the part that I know I reckon. I'm guessing Black knows about this place because of your past dealings with it?' both Black and Remus nodded.

'Past dealings?' asked Harry, but Hermione shushed him as Y/N pressed on.

'Well then. We saw the state of things downstairs and I think it's only fair that Ron and Harry get an explanation of that first. Harry especially. You both owe him that much. How did you find us Remus?'

'The Marauder's Map,' said Remus at once.

'You know how to work it?' asked Harry

'I helped write it,' said Remus matter-of-factly. 'I'm Moony, that was my friends nickname for me at school. Because… because I'm a werewolf.'

Harry's mouth fell open and Y/N heard Ron move around behind him.

'Me and Hermione have known since Snape's essay,' said Y/N quickly, 'but Remus was always good to me in classes. Never showed any ill-intent or ill-will, so I chose to keep it a secret. My curiosity got the better of me after reading about them and I asked him to fill me in on what happened to him, and he confirmed it to me.'

'Shows what we get for not talking to you two for a while,' said Ron from behind him. 'Get left out of the loop on a few things.'

'Remus isn't a bad person. At least I don't think so. It's why I really hope this explanation pans out,' said Y/N, turning back to Remus and Black.

'Well,' continued Remus, 'for as long as you all have, I believed Sirius to be a murderer. Not only of those in the street, but of Harry's parents. The man I thought I'd known for all those years betray his closest friends and the trust of the rest of us… it was a hard thing to face. Ever since then, I have believed that Sirius was a dangerous man who was in league with Lord Voldemort.'

Sirius gave a bark like laugh.

'However, when tonight came, I had a feeling you would all sneak down to visit Hagrid before his Hippogriff was executed. And I was completely right, I thought it best to keep an eye on you all. Make sure nothing bad happened and if something did I could be at the ready-' he gestured around at the room, 'so I watched the four of you enter Hagrid's hut. You stayed there for a while, then I saw three dots moving down towards the hut. You all disappeared out the back, but this time you were joined by another.'

'Scabbers,' said Y/N, turning to look at the rat.

'You already had a theory, Y/N?' asked Remus.

'Thanks to Black,' said Y/N, nodding towards him. 'I'm sure you heard about his break-in to the Common Room. He told me that he was after Scabbers and not Harry. I was confused, but I was already suspicious of Scabbers anyway. Crookshanks seemed to hate him from the moment he saw him, and Ron's sheets ended up covered in blood and ginger cat hairs on a day Crookshanks physically couldn't have done anything. We had him locked in a different room. He's also lived to well over twelve despite rats managing two to three years on average. We thought maybe we'd be able to see him on the Marauder's map, but you confiscated it before we could.'

'I wish you'd told me,' said Remus with a sigh. 'I would have been willing to let you look even if I did not let you take it and that may have sped things up. However, yes, the rat was with you when you left Hagrid's hut. But not under the name Scabbers.'

'What,' said the quartet blankly.

'I couldn't believe my eyes once I'd seen it,' Remus continued. 'I thought the map must be malfunctioning. There was no chance he was with you. But I didn't have much time to think. I saw another dot appear on the map and come sprinting towards you labelled Sirius Black. I watched him collide with you and watched as he dragged Ron and the other man down into the Whomping Willow. May I see Scabbers please, Ron?'

Ron looked to Harry, who in turn looked to Y/N.

'Remus. Black. If we let you see him, promise me you won't do anything until we know what's going on.'

Black opened his mouth, but Remus cut firmly across him.

'We promise. I won't even take him off Ron. I just wish to see him.'

Y/N looked back to Ron and nodded. Ron held up the still scrambling rat. It was fighting tooth and claw, doing everything it could to break free from Ron's grip and seemed to start squeaking louder as Remus leant in. He gave a strained almost victorious sigh.

'What?' asked Ron. 'What's up with him?'

'He's not a rat,' said Black from his position by the door.

'What do you mean?' asked Harry.

'He's a wizard,' said Remus.

'Another Animagus. Peter Pettigrew,' said Black.

There was a pause as the quarter digested this, then.

'But… Peter Pettigrew's dead,' said Harry. 'You killed him twelve years ago, didn't you?'

'I meant to. But little Peter got the better of me,' said Black, his eyes on the rat struggling within Ron's grip.

'Professor Lupin. If Peter is an Animagus, why has he never been registered? We looked through the register of those who have been previously, and Peter's name wasn't on the list,' asked Hermione.

'To be fair 'Mione, neither was Black's,' said Y/N, turning his eyes onto Black who gave a sort of half grimace.

'You're completely right, Hermione,' said Lupin with a warm smile on his face, 'but the Ministry never knew that there used to be three unregistered Animagi running around Hogwarts.'

'Do we have to tell the full story?' said Black, eyeing Scabbers. 'I'm so close to my revenge.'

'We owe it to Harry,' said Remus, 'and based off what I've heard, you owe it to Y/N as well. It's because of him that half the school didn't descend on you in the Gryffindor Common Room.'

Black's face tightened and he opened his mouth to talk but was interrupted by a creaking sound as the door crept open.

Y/N staggered.

His wand shot out of the end of his holster and he levelled it.

'Petrificus Totalus.'

There was a small exhalation followed by a dull thud and something in the area fluttered in and out of view.

'You need to be careful where you leave that damned cloak lying around, Harry,' said Y/N, backing up away from it. Hermione followed him backwards and forced a piece of chocolate into his hand. 'Remus, do us a favour and just grab where that was.'

Remus leant down and closed his hand around something. A moment later and the silvery invisibility cloak came away and Severus Snape was revealed face down under it, completely frozen.

'Stupefy,' added Y/N, and the jet of red light hit the stationary Potions master. He removed his own body bind and Remus rolled Severus over so he was now on his back.

'Severus is an extremely talented Wizard, Y/N. It's lucky that he must have forgotten about your ability. I think that might be the only reason you got away with that.'

'How did he even get the cloak?' asked Y/N, turning towards Harry who was looking oddly sheepish.

'After we went chasing after Ron I took it off, then when the tree hit me I dropped it. Didn't even think about it.'

'What are you all talking about Y/N's ability for? And why is Snape here?' asked Black, looking mildly curious. It was an odd expression to see on the gaunt face.

'I'll explain later. You first,' said Y/N as Hermione wrapped herself around his arm.

'Well,' began Remus, 'I suppose I had best start. I was a very small boy when I was first turned into a werewolf. My parents tried everything, but back in those days there was no cure. The Wolfsbane Potion that Severus-' he indicated the stunned Potions Master, 'has been making for me is a very recent discovery. It makes me safe, keeps me sane. As long as I take it in the week leading up to the full moon, I keep my mind when I transform. I am able to simply curl up in my office and wait for the moon to wane again.'

Harry was giving the stunned Snape an odd look. Y/N had a feeling it was because of him seeing the smoking goblet in Remus' office back in October.

'Before the Wolfsbane potion was discovered however,' continued Remus, 'I became a fully-fledged monster once a month. It seemed impossible that I'd be able to come to Hogwarts, other parents wouldn't want their kids exposed to me, but then Dumbledore became headmaster. He was sympathetic. He said that as long as we took certain precautions there was no reason I couldn't come to school. I told you months ago, Harry, that they planted the Whomping Willow the year I came to Hogwarts. It was planted because I came to Hogwarts.'

Harry's eyes spun onto Y/N and he grimaced slightly.

'Okay, maybe I wasn't fully honest when I told you why I knew about this tunnel. I didn't fully lie though. It was for the safety of the school,' he said.

'This house, the tunnel that leads to it. They were all constructed for my use. Once a month, I was brought out of the castle and into here to transform. The tree was placed over the entrance to stop anyone coming across me whilst I was transformed,' Remus continued. 'My transformations in those days were… terrible. It is very painful to turn into a werewolf. I was separated from humans, so I bit and scratched myself instead. The villagers heard the noise and screaming and assumed they were hearing very violent ghosts. Dumbledore encouraged the rumour.'

'And here I was, all excited to see the world's most haunted residence,' muttered Hermione.

'But transformations aside, I was happier than I had ever been in my life. For the first time ever, I had friends. Sirius Black, Peter Pettigrew and of course your father, Harry. James Potter. But much like Hermione and Y/N, my three friends did not take long to notice that I disappeared once a month. I made all sorts of excuse, like needing to travel home to visit my ill mother. I was terrified that they'd abandon me once they knew the truth. And once they'd figured it out, they didn't desert me at all. Instead, they did something for me that would make my transformations both bearable and the best times of my life. They became Animagi.'

'My dad too?' asked Harry, wide-eyed.

'Yes,' said Remus. 'It took them the better part of three years to work out how to do it. Your father and Sirius were the cleverest students in the school, and lucky they were, because the Animagus transformation can go horribly wrong. One of the reasons the Ministry keep a close watch on those attempting it. Peter needed all the help he could get. Finally, in our fifth year, they managed it. They could each turn into a different animal at will.'

'How did that help you as a werewolf?' asked Hermione.

'They couldn't keep me company as humans, so they kept me company as animals,' said Remus. 'A werewolf is only a danger to people. They snuck out of the castle every month under James' invisibility cloak.' He shook the cloak that was still in his hand slightly. 'They transformed. Peter was the smallest, he'd slip beneath the branches and touch the knot that freezes the tree. Then they'd slip down the tunnel and join me. Whilst with them, I became less dangerous. My body was still wolfish, but I seemed to regain some of my normality. Highly exciting opportunities were open to us now that we could transform. Soon, we were leaving the shack and roaming the school grounds by night. Sirius and James transformed into such big animals they could keep me in check. I don't think anyone discovered as much of the Hogwarts' grounds as we did. And that's how we came to write the Marauder's map and sign it with our nicknames. Sirius is Padfoot, Peter is Wormtail, James is Prongs.'

Harry seemed to open his mouth to say something, but Hermione spoke first.

'That was really dangerous though! If you'd gotten loose or given the others the slip-'

'A thought that still haunts me,' said Remus. 'There were near misses. Many of them, we laughed about them afterwards. We were young, thoughtless, carried away with our own cleverness. I sometimes felt guilty about having betrayed Dumbledore's trust, of course. He'd let me into Hogwarts when no one else would. And in return, I'd broken his rules and lead three friends into becoming unregistered Animagi. But it got tough to feel sorry when we sat down to plan our next month's adventure. And I haven't changed…'

Remus' face contorted as though he was sickened by himself.

'All this year I have been battling with myself, wondering whether I should tell Dumbledore that Sirius was an Animagus. But I didn't do it. I was too cowardly. It would have meant admitting that I'd betrayed his trust while I was at school, admitting that I'd led others along with me. And Dumbledore's trust has meant everything to me. Much as yours has, Y/N.'

Y/N looked Remus properly in the eye for what felt like the first time. There was a deep-set respect in there and he knew his reflected the same.

'Half the stuff I can even do now I can do because of your lessons, Remus. We've all done stupid things in school. I charged a basilisk with no weapon last year. Rushed a Professor with Lord Voldemort on the back of his head. I spent this morning out in the grounds with a wanted fugitive.' Black's face cracked into a slight smile. 'I know Dumbledore won't hold it against you. He's a good man. And at the end of the day, the decision was on your friends. You didn't lead them. They chose to follow.'

'He's right,' croaked Sirius, turning to look at Remus. 'We did what we did to support you. Not because you forced us to.'

'I wanted so hard to believe that Sirius had been using dark magic taught to him by Lord Voldemort to get into the school instead of his Animagi abilities, especially after the dagger we found. I didn't want to believe that what I'd done was helping him get closer to killing Harry. As much like the rest of you, I believed that was his end goal.'

'And what about Snape?' asked Harry, his eyes on Black. 'You spoke like you knew him.'

'I do,' said Black, his eyes travelling over the unconscious Potions master. 'What's he doing here, Remus?'

'He works at the school, Sirius.' His eyes turned onto the quartet. 'Sirius was at school with us. He fought very hard against my appointment to the Defence Against the Dark Arts position. He's been telling Dumbledore all year that I'm not trustworthy. He has his reasons, Sirius here once played a prank on him, a trick that nearly got him killed.'

Black made a derisive noise.

'It served him right. Sneaking around and trying to figure out what we were up to, hoping he could get us expelled.'

'Severus was very interested in where I went every month. We were in the same year, and he didn't like us very much. Nor did we him. He especially disliked James, jealous I think of his Quidditch talents.'

'Sounds familiar,' muttered Y/N.

'Snape saw me once going across the grounds with Madam Pomfrey. Sirius thought it would be amusing to tell Snape that all he had to do was prod the knot on the tree trunk with a long stick and he'd be able to follow me. Obviously, Snape tried it, if he'd managed to get as far as the shack he'd have run into a fully-fledged werewolf. But James stopped Snape and pulled him back, at great personal risk to himself. But Snape saw what I was. He was forbidden to tell anyone by Dumbledore, but he knew.'

'So that's why Snape doesn't like you?' asked Harry. 'He thought you were in on the joke.'

Y/N was exceptionally thankful for his gift. Who knows what would have happened had Snape still been conscious.

'May I ask my question now?' asked Black, turning towards Y/N. 'How exactly did you know Snape had walked in here? What is this ability? James was very proud of that cloak, we all were. Almost unstoppable under it, and you attacked as if it hadn't even been there.'

Y/N looked towards Remus for assurance and Remus gave an encouraging nod from behind Black's back. He hoped he wasn't making the wrong decision as he now looked at Black.

'It's an innate ability. My father could do the same, or so I've been told. I can sense powerful magical items. The cloak is one of the strongest I've ever been around. It goes off like a marker in my brain. Gives me a direction and, if I look close enough, I get an idea for the enchantment. When Harry first got the cloak, I almost passed out-'

'You did pass out,' said Ron from the bed. 'You collapsed backwards, you were in and out of consciousness for a good twenty seconds before we finally got the chocolate in you.'

'I can feel it almost anywhere it is. And Harry uses it that often I know the way it feels now. So the moment it entered the room-'

'You recognised it and knew someone must be under it,' said Black, turning back now to look at Snape 'Clever. Very clever. You're a very unique wizard, Y/N, you know that? Not many would stand face to face with me in the Common Room or spend a morning simply spending time and talking to a dog they'd never met before.'

'Thought it was weird when you wouldn't let me pet you,' said Y/N with a slight smirk and Sirius gave a bark of laughter. His face split into what genuinely looked like amusement for a moment, before it fell back into its sullen gaze and his eyes fell back onto Scabbers.

'There is one bit I don't get,' said Ron, looking at Black. 'If you broke out of Azkaban and came all this way for Scabbers, or Peter as you say, why now? He's been with our family for years.'

'That's a good point, Sirius,' said Remus, looking around. 'How did you find out where he was?'

Black reached into his robes and pulled out a crumpled piece of paper, which he smoothed out and held up to show them.

It was the photograph from the year prior of Ron and his family on holiday in Egypt, and there, on Ron's shoulder, was Scabbers.

'How did you get this?' asked Remus.

'Fudge,' said Black. 'When he came to inspect Azkaban, I asked to borrow his paper. And there was Peter on the front cover, I knew him at once. I'd seen him transform so many times. And the caption said he'd be going back to Hogwarts.'

'He's at Hogwarts,' said Harry quietly.

'My God,' said Remus, looking between the paper and Scabbers. 'He's missing a toe.'

'He's been missing it for as long as we've had him,' said Ron.

'He cut it off himself,' said Black, 'just before he transformed. I cornered him and he yelled for the whole street to hear that I'd betrayed Lily and James. But before I could curse him, he blew apart the street with his concealed wand. He killed everyone within twenty feet of himself and sped down into the sewers with the other rats.'

'Didn't any of you ever hear?' asked Remus 'The biggest part of Peter they found was his finger. He must have cut it off himself.'

'And what about Crookshanks?' asked Y/N, nodding over towards the cat. 'Black says they've been working together.'

'Crookshanks is the most intelligent of his kind I've ever met,' said Black, gazing fondly at the ginger cat. 'He recognised Peter for what he was straight away. And when he met me, he knew I was no dog. Took me a long while to make him trust me, but finally I managed to communicate with him what I was after. He's been helping me.'

'That's why he took my wand but gave it back once you'd gone,' said Y/N, looking towards the cat, who purred loudly. 'He didn't want me to stop you taking Scabbers, but he didn't want us to just let you go.'

'He kept trying to get Peter for me. After it kept proving unsuccessful, he stole the passwords to the Gryffindor dorm for me. And that's when I ran into Y/N, he told me that Peter had left. Faked his own death and attempted to blame it on Crookshanks on a day that Crookshanks had been locked in a room. Faking his death had worked before…'

'We picked the right day for it,' said Y/N. 'Who knows what would have happened if this had've all played out differently.'

'But I don't get it,' said Harry. 'We were told you were my parents Secret-Keeper, that you had to tell on them to Voldemort for him to find them. Now you're saying Peter did it?'

'Harry…' said Black slowly. His face was suddenly hurt, grief stricken. 'I was too obvious. Voldemort would know they'd named me. And if not me, then he'd surely go for Remus. You have to understand. I never thought he'd target Peter. They'd see him as too weak. I convinced them to switch to Peter for the Secret-Keeper at the last moment. The night they died, I arranged to check on Peter. But once I got to where he was meant to be hiding, he was gone. There was no sign of a struggle. I hurried to your parents house and when I saw the house destroyed… and their bodies… I realised what Peter had done. What I'd done.' His voice broke and he turned away.

'Words are pointless now,' said Remus. 'Actions will explain the rest. Ron, please, give me Scabbers. We shall force him to reveal himself. If our theory is wrong, he will be unharmed.'

'Are we sure about this?' whispered Hermione.

'No,' whispered Y/N, 'but we don't have another choice. Their story adds up more than anything else we've heard all year. And we need answers.'

Ron was looking to Harry, who gave him a firm nod. Then he took a deep breath and held out Scabbers.

Remus took him and Scabbers began flailing even faster, his eyes were practically bulging out of his head.

'Ready Sirius?' asked Remus.

Black moved over towards Snape and began rooting around in his pockets. A moment later and he straightened up with Snape's wand clutched in his hand and nodded.

'Together?' he said quietly.

'I think so,' said Remus. He held Scabbers between them and raised his wand. 'On three. One, two, THREE!'

A flash of blue-white light burst from both wands and hit the struggling rat. Remus released his grip and, for a moment, Scabbers was left there, frozen in mid-air. Then, his form began to twist and morph. The rat fell and hit the floor, but it wasn't a full rat anymore. A head was beginning to spring from where Scabbers' head had been. His paws were elongating and turning into hands. His figure was growing.

Finally, there was a man standing where Scabbers had been. Y/N could see now why he had taken the form of a rat. Or perhaps he had simply lived as a rat for too long. He was very short, his hair was ragged, colourless and missing several patches. He had a very pointed nose and very watery eyes, and his eyes immediately began scanning the room. Y/N's wand shot out of the end of his holster and he pointed it at the door.

'Colloportus.' There was a click and Pettigrew threw him a dirty look as he stashed the wand back away in his holster.

'Well hello Peter,' said Remus pleasantly. 'Long time no see.'

'S- Sirius, R-Remus,' Even the voice was squeaky. 'My friends, my old friends.'

Black began to draw the wand back, but Remus placed a hand in front of him with a look and then turned back to Pettigrew.

'We've been having a little chat, Peter, about what happened the night Lily and James died. You may have missed the finer points whilst attempting to scrabble around down there.'

'Remus!' gasped Pettigrew. 'You don't believe him, do you? He tried to kill me. He's come to try and kill me again! He killed Lily and James and now he's going to kill me too!' Pettigrew pointed accusingly at Black, and Y/N spotted that his index finger was missing.

Black's face was impassive. He simply stared at Pettigrew. That in itself was a terrifying enough sight. A man who had been at the mercy of the Dementors for twelve years wasn't exactly someone who looked inviting.

'No one's going to try and kill you until we've sorted some things out,' said Remus.

'Sorted things out?' squealed Pettigrew as his eyes strayed across the boarded-up windows. 'I knew he'd come for me! I knew he'd be back for me! I've been waiting for this for twelve years!'

Y/N felt sceptical at this and apparently, so too did Remus as he asked.

'You knew Sirius was going to break out of Azkaban? Despite no-one having ever done it before?'

'He's got dark powers the rest of us can only dream of! How else did he get out of there? I suppose He-Who-Must-Not-Be-Named taught him a few tricks!'

Sirius gave a laugh. A harsh, cold, bone-chilling laugh.

'Voldemort? Teach me tricks?' Pettigrew flinched. 'What? Scared of your old master's name?' taunted Black. 'I can't say I blame you. His lot aren't very happy with you, are they?'

'Don't know what you mean, Sirius-' began Pettigrew.

'You've not been hiding from me for twelve years,' said Sirius, stepping forward. 'You've been hiding from Voldemort's old supporters. I heard things in Azkaban, Peter. They all think you're dead, or you'd have to answer to them. You sent Voldemort after the Potters and Voldemort met his downfall there. And after the earlier failure with your group going after Maria-'

'What did you say?' said Y/N, quickly stepping forward. 'This rat went after Maria?'

'Him and a group of Voldemort's finest were sent to track her down and kill her, whilst Voldemort went after a man called D/N. Both abandoned him at the same time for each other. Peter was sent with three others,' said Sirius.

'Maria Vilian?' asked Y/N.

'Yes, that was her name when with the Death Eaters.' said Sirius. 'I believe she and D/N married later. How do you know of her?'

But Y/N's eyes were now on Peter.

'What did you do to her?'

But it was Remus who answered him.

'Maria took down her four attackers with ease, Y/N. I was sent by Dumbledore to look after her after D/N… after he was found dead. She is alive, don't worry.'

'I don't get it,' said Harry. 'Why do you know who she is, Y/N?'

'Maria Vilian is her maiden name. Her current name is Maria L/N. She's my mother, Quirrell and Voldemort told me back in our first year.'

A ringing silence followed Y/N's words and then he heard Black snarling.

'So not only did you strip Harry of both his parents that night, but you tried to take Y/N's mother from him too? And I thought you could sink no lower.'

'I'd seen your official surname, but my mind never made the connection. She was always Vilian to me. That was how we'd always known her whilst she'd been in league with Voldemort. I'm sorry Y/N, I should have said something,' said Remus.

'I don't expect you to bridge every gap, Remus,' said Y/N, his eyes on Pettigrew. 'Well, rat,' he practically spat that work at Peter, 'at least give Harry the decency of telling him why you decided to strip him of a proper childhood.'

'You can't believe this madness!' said Pettigrew, turning to face Y/N. 'Why would I be sent after your mother? And James and Lily were my friends! You heard from Remus and Sirius that I am not a capable wizard. Sirius is far more likely to have been capable of it.'

'The same night Voldemort fell, he tried to kill me. Tried to teach me a lesson for what my father and mother had done. Sirius has had two opportunities now to kill me and get away with it with no backlash, and on neither has he taken it. You've been in hiding as a rat for twelve years,' snarled Y/N.

'Because I was scared!' wailed Pettigrew. 'I helped put one of Voldemort's biggest supporters in Azkaban-'

But he didn't get to finish the rest of his sentence as Black snarled at him.

'How dare you. I, a spy for Voldemort? When did I ever sneak around people who were stronger and more powerful than myself? But you, I don't know how I didn't see you were the spy from the start. You always liked big friends who could look after you.'

Y/N felt Hermione wrap her hand in his and step up next to him. She squeezed it and he looked down at her, she had tears swimming in her eyes. He pulled her into a small hug and once they'd broken apart, she spoke.

'Can- can I say something?' she asked.

'Certainly Hermione,' said Remus.

'Well, Pettigrew has been sleeping in a dorm room with both Y/N and Harry for years now. If he's working with… Voldemort. How come he's never tried to hurt Harry or Y/N before?'

Y/N glanced at her astonished, it was the first time he'd heard Hermione say his name out loud. She gave him a small smile.

'You see?' said Pettigrew shrilly. 'I have never hurt a hair on either of their heads. Why should I?'

'He never did it because he's never done anything for anyone unless he could see what was in it for himself,' snarled Black. 'Voldemort's been in hiding for years. Most say he's half dead. You weren't about to risk everything for a master who may never return and had lost all his power. You'd want to be quite sure he was mighty again before making your move. That's why you stayed with a wizard family, isn't it? To ensure you knew if and when he was rising once again.'

Pettigrew was moving his mouth silently. He'd been caught out again, and his proclamations of Sirius being truly the one at fault were getting tougher to believe. Especially after Hermione's next question.

'And… Mr Black? Sirius? How did you get out of Azkaban if you didn't use dark magic? As long as you don't mind me asking.'

'Of course not,' said Sirius. His face was warmer than it had been for most of the evening upon being addressed so formally, but it grew colder again as his eyes span onto Peter. 'I can't say I fully know how I did it,' he said. 'I think the only reason I never lost my mind was because I knew I was innocent. It wasn't a happy thought so the Dementors couldn't take it from me, but I knew I wasn't in the wrong. It kept me sane, and knowing who I was helped me keep my powers. So, when it all became too much, I curled up in the corner of my cell as a dog. Dementor's can't see. They feel there way towards people using emotions. They could tell my feelings were less human as a dog, but they just assumed I was going mad like the rest. But I was weak, there was no way I was able to drive them back. But then-'

Sirius turned his murderous eyes onto Pettigrew, who shrunk away a bit.

'I saw Peter in that picture. Saw that he was at Hogwarts with Harry. Perfectly positioned to strike if he needed to, if any word of Voldemort returning reach him. And who'd dare question his loyalty if he brought the last Potter to Voldemort. It lit a fire in me. I knew I had to do something, I was the only one who knew he was still alive. Again, it wasn't a happy feeling, but it was an obsession. It gave me strength. So, one night when they opened my cell, I slipped past them as a dog. It made me much harder for them to sense, they were confused. I swam back to the mainland and journeyed north. I slipped into the Hogwarts grounds using the secret tunnel and have been living in the forest ever since. Except for when I come to watch the Quidditch. You fly well, Y/N. And you Harry, you fly as well as your father did.'

Harry and Sirius held each other's gazes.

'Believe me. Please,' said Sirius. 'I would never betray James and Lily. I would have died before I betrayed them.'

Harry swallowed hard, and then nodded.

'No!' squealed Pettigrew. He collapsed forward, clutching at the hem of Sirius' tattered robes.

'Sirius! It's me! Peter, your friend. You wouldn't-!'

But Sirius threw a kick at Pettigrew and he recoiled.

'There's enough filth on my robes without you touching them,' he snarled. So instead, Pettigrew turned his attention onto Remus.

'Remus! You don't believe him, do you? Sirius would have told you if they'd changed the plan.'

'Not if he thought I was the spy,' said Remus. 'I assume that's why you didn't tell me?' he asked Sirius.

'Forgive me, Remus,' he said.

'Not at all Padfoot, old friend,' Said Remus, rolling up his sleeves. 'And will you, in turn, forgive me for believing you were the spy?'

'Of course,' said Sirius as he began to roll up his own sleeves. 'Shall we kill him together?'

'Yes, I think so,' said Lupin grimly.

'You wouldn't, you won't…' gasped Pettigrew. And he scrambled around to Ron. 'Ron? Haven't I been a good friend, a good pet? You won't let them kill me, Ron, will you? You're on my side, aren't you?'

But Ron was staring at Pettigrew with the utmost revulsion.

'I let you sleep in my bed!' he said.

'Kind boy, kind master...' Pettigrew crawled toward Ron, 'you won't let them do it. I was your rat I was a good pet.' But Ron threw a kick at Pettigrew with his broken leg. Y/N was grateful he'd been able to somewhat repair it.

Pettigrew turned on his knees, staggered forward, and seized the hem of Hermione's robes.

'Sweet gir-' was all he managed before he squealed in pain and scrambled backwards.

'If you dare, EVER, lay a finger on her again, I will be the one to kill you, Pettigrew,' snarled Y/N, his wand still aimed at Pettigrew's throat.

'Strong Y/N. Gifted Y/N. You wouldn't let them hurt me, would you?'

'The alternative is letting you go back to Voldemort and tell him everything you know about all of us. I think I'd rather you kept that mouth shut,' snarled Y/N.

'I won't tell him anything! I won't! He'll be none the wiser!'

'A confession? So it was you. And I assume that means you were also sent after my mother?'

'I didn't want to hurt her!' wailed Pettigrew. 'He made me do it-'

'Traitor,' spat Y/N and he turned away.

'Harry… Harry… You look just like your father-'

But again. Pettigrew was interrupted.

'HOW DARE YOU SPEAK TO HARRY?' roared Sirius. 'HOW DARE YOU FACE HIM? HOW DARE YOU TALK ABOUT JAMES IN FRONT OF HIM?'

'Harry,' whispered Pettigrew, shuffling toward him. 'Harry, James wouldn't have wanted me killed... James would have understood, Harry. He would have shown me mercy.'

Both Sirius and Remus strode forward, seized Pettigrew's shoulders, and threw him backward onto the floor. He sat there, twitching with terror, staring up at them.

'You sold Lily and James to Voldemort,' said Sirius. 'You have already admitted to it.'

Pettigrew burst into tears. 'Sirius, Sirius, what could I have done? The Dark Lord... you have no idea. he has weapons you can't imagine. I was scared, Sirius, I was never brave like you and Remus and James. I never meant it to happen. He-Who-Must-Not-Be-Named forced me—'

'DON'T LIE!' bellowed Sirius. 'YOU'D BEEN PASSING INFORMATION TO HIM FOR A YEAR BEFORE LILY AND JAMES DIED! YOU WERE HIS SPY!'

'He-he was taking over everywhere!' gasped Pettigrew. 'Wh-what was there to be gained by refusing him?'

'What was there to be gained by fighting the most evil wizard who has ever existed?' said Sirius, with a terribly fury in his face. 'Only innocent lives, Peter!'

'You don't understand!' whined Pettigrew. 'He would have killed me, Sirius!'

'THEN YOU SHOULD HAVE DIED!' roared Sirius. 'DIED RATHER THAN BETRAY YOUR FRIENDS, AS WE WOULD HAVE DONE FOR YOU!'

Black and Lupin stood shoulder to shoulder, wands raised.

'You should have realized,' said Remus quietly, 'if Voldemort didn't kill you, we would. Good-bye, Peter.'

Hermione turned to Y/N and buried her face into his chest. He wrapped his arms around her, shielding the sight of Pettigrew from her view. But then-

'NO!' Harry yelled. Running forward and placing himself in front of Pettigrew, facing the wands. 'You can't kill him.'

Sirius, Remus, Ron, and Y/N all looked staggered. Hermione lifted her head tentatively to watch the room.

'Harry, this piece of vermin is the reason you have no parents,' Sirius snarled. 'This cringing bit of filth would have seen you and Y/N die too, without turning a hair. You heard him. His own stinking skin meant more to him than both of your families.'

'I know, We'll take him up to the castle. We'll hand him over to the Dementors... He can go to Azkaban, but don't kill him. You alright with that?' he added to Y/N.

Y/N took one long look at the mass that was Pettigrew and felt the arms around his chest tighten. He took a deep sigh.

'It's not my call. He only tried to kill my mother. He actually got both of yours killed. This is far more your right than mine.'

'Harry!' gasped Pettigrew, and he flung his arms around Harry's knees. 'You - thank you, it's more than I deserve, thank you-'

'Get off me,' Harry spat, throwing Pettigrew's hands off him in disgust. 'I'm not doing this for you. I'm doing it because- I don't reckon my dad would've wanted them to become killers, just for you.'

Remus and Sirius shared a look for a few moments, and Y/N thought they were going to strike anyway. Then they both lowered their wands.

'You're the only person who has the right to decide, Harry,' said Sirius, 'but think- think about what he did.'

'He can go to Azkaban. If anyone deserves that place, he does.'

'Very well,' said Remus. 'Stand aside, Harry. I shall tie him up.'

Harry moved aside and long ropes spread from the end of Remus' wand. A moment later, Pettigrew lay struggling against his new bindings on the floor. Y/N raised his wand and pointed it at the door.

'Alohomora.'

'Right,' said Remus. 'Ron, I can't do anymore with that leg than Y/N did so it's probably best to stick it in a cast and get you back up to the castle.' He moved over to Ron and muttered 'Ferula' so bandages spread around the ankle into a makeshift cast. Ron got to his feet gingerly with Remus' help and didn't wince.

'That's better,' he said, 'thanks Professor, thanks Y/N.' Y/N merely nodded.

'What about Professor Snape?' asked Hermione, her voice still slightly muffled as she spoke into Y/N's chest.

'I don't imagine Y/N's stunning spell is too potent. No doubt it'll be wearing off by itself soon. Talented wizard or not, you are still only a third year. Still. Best not to wake him. We will take him like this; Mobilicorpus,' said Remus and Snape's body animated up as though a puppet on strings.

Suddenly, Y/N watched his world flip upside down. It was lucky Hermione was still wrapped around his chest because it meant she was there to balance him immediately.

He'd forgotten that the cloak had been out the entire time. The adrenaline and fascination in the story had been helping him ignore the worst of it. But now that they were preparing to leave, it all came rushing back and his head pounded horribly.

'Come on,' said Hermione's voice, she sounded terrified. A moment later and he felt a second stronger arm on his other side. He looked around to see Sirius helping to prop him up.

'Thanks,' he said dazedly.

'Two of us should be chained to that,' said Sirius, nodding towards the blurry mass that was Pettigrew.

'I'll do it,' said Remus.

'And me,' said Ron, moving forward.

Y/N heard the clinking of metal as he felt Hermione press another piece of chocolate gently against his mouth. He took it from her and chewed as the room drifted slowly the right way up. He saw Remus attaching Ron to Pettigrew. Ron's face looked set and angry. He seemed to have taken the reveal of Scabbers as a personal insult.

As Y/N lifted himself gingerly up and Sirius quickly helped rebalance him before moving off a little, Crookshanks hopped off the four-poster bed and made his way out of the bedroom, his tail held high.