It was the strangest reunion of godfather and godson. Harry sat in snow in front of the Shrieking Shack, his friends flanking him, Sirius glaring down at him.

The look of surprise changed from godfather to godson. Now it was Harry's turn to stare at the altered appearance of the man before him. His eyes held a spark of life that had not been there before. He was dressed in muggle clothing, his beard was trimmed, hair still long, but clean and healthy-looking. Overall, he looked a lot healthier – younger, even. Almost like a different man.

During the ensuing awkward moment, Harry's face caught up with his brain and he grimaced, while the glare melted off Sirius' face, changing into something uncertain. It occurred to both of them that despite all the letters they had exchanged, all they had told each other, this was only the second time since Sirius' escape from Azkaban, that they had met face to face.

Sirius was the first to look away. He visibly drew back, distancing himself, reminding himself that he must still be a stranger to Harry. He closed his eyes and pinched his nose. "I cannot believe I fell for that," he muttered with an exhale that was half laugh, half sigh. "Told you half a dozen ways to sneak out of school…"

"I, er..." Harry felt his cheeks redden at the reminder of how he had manipulated Sirius.

Before he could begin to explain himself, though, there was a deafening BANG and an onslaught of blinding light. Sirius' curse turned into a bark as he morphed into Padfoot and jumped out of the way. A second later, a gigantic pair of wheels and headlights screeched to a halt exactly where he had just been standing. They belonged, as Harry saw when he raised his head, to a triple-decker, violently purple bus, which had appeared out of thin air. Gold lettering over the windshield spelled The Knight Bus.

"Oh, wow, it really just appeared out of thin air!" said Hermione in wonder.

A conductor in a purple uniform leapt out of the bus and began to speak loudly over their heads. "Welcome to the Knight Bus, emergency transport for the stranded witch or wizard. Just stick out your wand hand, step on board, and we can take you anywhere you want to go. My name is Stan Shunpike, and I will be your conductor this morn-"

The conductor stopped abruptly. He had just caught sight of Padfoot, standing next to Harry, who was still sitting on the ground. Harry scrambled to his feet. Close up, he saw that Stan Shunpike was only a few years older than he was, eighteen or nineteen at most, with large, protruding ears and quite a few pimples.

"Woss that beast?" he said, dropping his professional manner to stare with a fascinated horror at Padfoot.

"He's my dog," Harry said after a pause. "Er, can he come along?" Padfoot nudged him, shaking his head and trying to push him away from the bus. He stopped, though, as Stan Shunpike began to edge away from him.

"'s big for a dog..."

"He's well-behaved," said Hermione. Ron nodded.

"He'll need an extra ticket," Stan said, shooting the dog uncomfortable looks. "'e looks like a..." he muttered, not voicing the rest, though his lips still shaped the word 'grim'.

"That's fine," Harry said quickly. "How much would it be to get to London?"

"Eleven Sickles each," said Stan, "and the dog counts as a passenger. But for firteen you get 'ot chocolate, and for fifteen you get an 'ot-water bottle an' a toofbrush in the colour of your choice."

They paid and settled into their seats. There were not many passengers, only a couple of elderly witches who were quietly chatting in the farthest seats back, and an ancient-looking wizard sat directly behind the driver. Ernie Prang, the driver, himself an elderly wizard wearing very thick glasses, would occasionally shout something at him. (He was very hard of hearing, apparently.)

Harry, Ron and Hermione spent the journey sitting quietly somewhere in the middle, trying not to spill their hot chocolate on themselves (they had all bought one), as the bus lurched and turned this way and that, and to ignore Padfoot's rather vicious-sounding growling at their feet.

All in all, they were all happy when the journey was finally over and the bus skidded to a halt in front of the Leaky Cauldron.

A moment later, when the bus had left, and Padfoot began pulling him – with his teeth – away from the pub and towards a secluded alley, Harry began to reconsider.

"Sirius, wait!" hissed Ron, as he and Hermione ran after them.

"You don't understand!" began Hermione in a panicked voice. "We had to come to Diagon Alley!"

"Ah, did you now?" Sirius began answering back as soon as he had shifted. "And what dire circumstances, may I ask, forced you to sneak out of school and travel all the way to London?!" His voice rose as he talked, ending on a shout directed at his godson.

Harry looked around, fearing to be overheard. "We, er, need to buy the powdered horn of a bicorn."

"For the polyjuice potion," chimed in Hermione. "I know Harry wrote to you about that..." She trailed off as Sirius shifted his attention to her, frowning uncomprehendingly.

"The – wait. Wait. You were going to brew that thing ages ago-"

"We started brewing it ages ago, you mean. You know what polyjuice potion is, right?" asked Ron.

"Yes, of course I know what it is! But I've never brewed it. Potions was never my – Never mind. Just how complicated can it be? You're second years!"

"Well, it does take a couple months to brew—" said Harry.

"You can only learn about it in the forbidden section!" added Ron.

"It's not particularly difficult." Hermione rolled her eyes. "As long as you follow the instructions very carefully and take care with the more volatile ingredients—"

"Volatile—" Sirius expelled, but then stopped himself. The muscles in his cheek twitched, and slowly, involuntarily pulled into a smile. "Wait. So you really are brewing some far too advanced potion – that you shouldn't even have heard of – and you haven't messed it up so far?"

"No, we haven't. And all that work would be wasted if we can't get the bicorn horn in time," said Hermione imploringly, willing him to see their point of view.

"That's—" Sirius stopped, shook his head. "Alright, I am impressed. But! This does not change the fact that you did something completely outrageous!" But despite his words, it had changed something for him. His tone was sounding more impressed, his admonishment more perfunctory than truly meant.

Harry picked up on this and breathed a sigh of relief. "Well, now that we're here, though... er, you don't mind if we go and buy what we need, do you?"

Sirius shook his head, but before Ron and Hermione's protesting looks could turn into arguments, an unexpected, snorting laugh escaped him. "Oh, alright, then. If you're doing this, you might as well do it well. Can I borrow a wand?"

Harry held out his with a quizzical look.

"I did manage to scare up a wand, actually," Sirius went on to say, while he began waving his wand around Ron. "But in case something happens, I'd rather not leave its trace around any of you."

Harry was not sure he was following this explanation, but he had no trouble figuring out what Sirius was doing: Ron's appearance was changing in front of his eyes, looking years younger all of a sudden, hair turning brown and Hogwarts scarf turning a nondescript colour of grey. Next came Hermione.

"I don't think many people would recognise a muggleborn, but in case someone feels the need to talk about you and describe you to someone who might recognise you..." With this, Sirius visibly deaged Hermione and turned her hair short and blonde – though still bushy. "No use trying to tame it. It never works," he said, but did not explain further.

"Just how did you hope to disguise yourselves without my help?" he asked when it was Harry's turn.

"Just like you said, no one will recognise Hermione. She was going to buy the ingredients. I have my invisibility cloak with me for me and Ron," explained Harry, while wondering what he now looked like.

"Oh, for—" Sirius grimaced. "You have to be better prepared than that! Hogwarts aged children in Diagon Alley at this time of the year — Really, if you leave so many things to chance — I can't believe I'm explaining this to you," he muttered to himself, shaking his head. "Now, don't take this to mean that I condone what you did, or any future rule-breaking, because I don't! But—" He grimaced again.

"But, er, just this once, just so we can do things properly…" Harry said carefully, eager to hear more, but unwilling to push his luck.

Sirius regarded them with a frown, that deepened to a scowl. "Properly, you say," he finally said with a decisive shake of his head. "Confound it! You're right. You're spending an unauthorised Hogsmeade weekend in London! You might as well make the most of it. And having an adult with you will make things easier." With that, he returned Harry's wand and then pointed his own wand at himself.

"Now, the thing about transfiguration spells is that they're by their very nature unstable," he explained. "Especially human transfiguration. We won't be able to do any magic while transfigured and no matter how careful we are, the spells might fail any minute. So, stay close to me, and let's be in and out of the shop as quickly as we can…"

The little group of people who left the Leaky Cauldron through the backyard a little while later blended in well enough with the other visitors of Diagon Alley. It was a Saturday, and there were plenty of people come to shop, including parents with their children. No one paid the group of four any mind, and it was only partly due to the various spells that they were blanketed in, thick as cloaks.

Half an hour later, the four of them were sitting in a muggle cafe, not too far from Diagon Alley, the adolescents having hot chocolate, and Sirius drinking a cup of coffee. Sirius had dropped all pretence of responsibility with the change of appearance. He was laughing boisterously, sounding oddly like a barking dog, suggesting even more outrageous ways to spend the rest of their day than the adolescents themselves.

"What were you doing in Hogsmeade, anyway?" asked Harry, after they were done planning.

Sirius visibly sobered at the question. "Looking for Pettigrew, of course. I followed his trail to the village, but either it's been too long, or there are too many magical signatures there. Either way, I lost the trail there. For the moment," he added, and it sounded like a promise.

His young listeners exchanged looks.

"You think he's headed to Hogwarts?" asked Ron.

"I don't see why he would," Sirius replied slowly. "I have considered it, myself, but it seems such an unlikely thing to do. I wasn't sure if it was worth the risk of going to Hogwarts to check. Not that Peter was ever known for his careful planning… And not like I can be relied on to guess what he's up to, anyway." He shook his head, to dispel the bitter thoughts. "But even so, going back to a place where so many people could recognise him… Why? What possible reason could he have?" He frowned.

"Well, maybe if you check over the holidays, when there's not too many people around to spot you — just in case," said Hermione.

"Maybe. But for now, let's have fun. If you're finished with your drinks, let's go catch the bus."

It was a good thing that Sirius had managed to acquire money (though none of them had been brave enough to ask him how). Harry had been glad to have avoided going into Gringotts, even though he had brought his vault key along, but he had been worried that the goblins might recognise the vault number. Sirius had immediately waved aside the idea of Gringotts, anyway, and seemed quite happy to pay for everything, including more Knight Bus tickets for the three adolescents and Padfoot.

They emerged from the bus in Surrey, not too far from where the Dursleys lived. They were some distance away, as the Knight Bus avoided stopping in large open areas, no matter what Stan Shunpike thought about the muggles' observational skills. The large building was easy enough to spot, even from a distance.

Sirius had barely changed back into his human form when he drew his wand and transformed yet again, this time into an uncanny resemblance of Vernon Dursley. "What do you think? Will I pass?"

Harry nodded, looking nothing short of disturbed.

Sirius left the three friends there, while he made his way to the Smeltings Academy. While they waited, Harry and Ron tried to guess at Dudley's reaction when his 'dad' turned up to take him out of school. Hermione mostly ignored them, and seemed much more interested in the powdered bicorn horn they had bought earlier. A short while later, they saw the shape of Vernon Dursley coming towards them, moving faster than Harry had ever seen before, with Dudley trailing after him, trying to keep up. As soon as the blond boy spotted his cousin and his two friends, he stopped in his tracks. Harry laughed in response and waved him over.

"Harry? What is going on?" Dudley began to say, before he had even reached them, not stopping to draw breath first.

Sirius, with his much larger body presently, urged him along, out of sight from the school, and before Harry had time to explain, turned into Padfoot. He barked enthusiastically while Dudley screamed, and chaos reigned as Harry and his friends tried to explain amid their laughter. Finally, they reached the point in their tale when Padfoot, formerly Snuffles, turned out to be a wizard.

"I wanted to tell you," said Harry. "Really, I did. But I didn't want to write all this in a letter. What with Sirius being on the run and Pettigrew still around — and Dobby, of course—"

"Aw, man. And I thought I'd been following all your adventures this year. But I didn't know so many things…" Dudley sounded disappointed.

"Well, I think I can ward my letters a little better than those three," said Sirius. "If you don't mind more letters from the wizarding world, I could keep you up to date as well—"

"Oh, would you? That'd be so great!"

"Of course. I wanted to tell you myself. I wanted to thank you, for being so brave this summer, for saving Harry from that awful situation, but I didn't know how to contact you, how to tell you who I was without frightening you."

"Oh, that," said Dudley, trying to sound casual, but looking obviously pleased.

"And now that you scared him anyway," said Harry with a pointed look at his godfather, "maybe we should get going. We were thinking, maybe we could go back to London, maybe watch a film, and Hermione wanted to do some sightseeing—"

"Ah, and you wanted to take me along?" Dudley did not sound particularly enthusiastic at the prospect.

"Well, only if you wanted to." Harry frowned. He liked his school, as opposed to Dudley, but even he would enjoy sneaking out for a day to have fun.

"I do," Dudley groaned. "But I had a match today…"

"Oooh, that muggle sport, was it?" asked Ron.

"Is there a boxing competition today?" asked Hermione.

"Sort of. Not a proper one, that'll be at the end of the year, but…"

"Can we watch?" asked Harry.

"I don't think so. There aren't any visitors today. That'll be later, in the summer—"

"Oh, I'm sure your headmaster wouldn't mind your 'dad' watching — he seemed very eager to curry favour with, er, me," said Sirius.

"And we can use Harry's invisibility cloak," said Ron, nodding.

This did not delay them for very long, because Dudley lost early on. It took a little longer for Sirius to get away from the headmaster's reassurances that Dudley would soon be doing better, but eventually he extricated himself. Once they had left the school and he was back to his usual appearance, Sirius borrowed the cloak from Harry and went back.

"I made sure the headmaster won't think to tell the real Vernon Dursley about this," he explained when he came back.

They took muggle transport to London, so as not to draw too much suspicion from the people on the Knight Bus. It was later in the afternoon when they got there. Harry thought Christmas shopping might be a good idea, and his cousin and friends agreed. They all tried to hurry, but by the end of it, they did not have too much time left until they had to go back, so Sirius decided they would only do one more thing. Hermione was a bit put out, but the boys' votes for cinema won. Dudley wanted to see Home alone 2, as he had enjoyed the first part. Hermione rolled her eyes, but the other two boys agreed, as they had no preference themselves.

With large bowls of popcorn, courtesy of Sirius again, they settled into their seats to watch the film. Harry and Hermione made sure to tell Ron what to expect, so he would not draw attention to them. Ron stayed perfectly silent inside the cinema, but as soon as they were outside, he began to bombard them with questions, everything from how alarm clocks worked in the muggle world to how a film was made, sounding quite a bit like his father.

"I should not have let you watch that," Sirius muttered to himself, but immediately had four pairs of indignant eyes on him. "What! Like you lot need to come across any more bad ideas." He shook his head, but the youngsters ignored him, continuing with their enthusiastic discussion of the film.

Sooner than any of them liked, the short winter day turned into evening, signalling it was time for Dudley to go back to his school, and for Sirius to say goodbye. He did not take the Knight Bus back to Hogsmeade with them, saying his goodbyes together with Dudley, before disapparating to places unknown. Honeydukes was almost empty when the three friends sneaked in, covered by the invisibility cloak. The way back through the tunnel seemed even longer, exhausted as they were from their long journey. But Hermione would not let them rest until they had added the bicorn horn to the potion.

The had barely left the statue out of sight when they ran into Snape. He looked straight at them, as they walked past him, his gaze following them until they were out of sight, inscrutable. They continued chattering about the day's events as soon as they were past him, none of them mentioning their unease at the encounter.

"Well, this is it," she said, after adding the bicorn horn. "The rest should be easy enough. We just have to wait a little longer."

Elated, they walked to their dorm, reminding each other to keep their voices down, because everything they wanted to talk about involved rule-breaking of one form or another.

~HP~

The panic that had reigned in school after Ginny's attack had settled down somewhat, but not enough to stop students from wanting to go home. Everyone seemed to be in a hurry to book seats on the Hogwarts express to go home for Christmas.

Harry was of course staying, but so were his two friends and the elder Weasley boys. Ron's parents meant to visit Bill in Egypt, but thought it better for their remaining children to stay closer to Ginny in the hospital wing.

At last the term ended, and a silence deep as the snow on the grounds descended on the castle. Harry found it peaceful, rather than gloomy, and enjoyed the fact that he, Hermione, and the Weasleys were almost the only people left in the Gryffindor Tower, which meant they could play Exploding Snap loudly without bothering anyone, and practice duelling in private.

Perhaps they grew careless with the added freedom, forgot to check their voices when talking about their secret plans. Or maybe Snape had been keeping them under close watch for so long, that it was bound to happen eventually.

A couple days before Christmas, Hagrid arrived late for dinner in the Great Hall, his face entirely hidden by a woolly, snow-covered balaclava, and wearing his moleskin overcoat. A dead rooster was hanging from one of his massive, gloved hands.

"Hagrid, what is the matter?" Dumbledore asked from his seat behind the high table.

Hagrid held up the limp rooster. "Second one killed this term, Professor," he explained. "It's either foxes or a Blood-Suckin' Bugbear, an' I kept looking ter find any traces around the hen coop. Must have forgot the time." He looked chagrined, as he finally noticed everyone's eyes on him. He glanced at the dead rooster in his hand, only now noticing how out of place it was.

"Put that away, Hagrid, and come have dinner," said Dumbledore. "We can talk about it later."

But despite his words, the teachers seemed to be talking about it to Hagrid all through dinner. When Harry and his friends were leaving the Great Hall, they heard Flitwick offering Hagrid to put some charms around the hen coop. Dumbledore then turned to Snape and asked him if he would be willing to help as well. "Perhaps some sort of a trap with a sedative in it," he suggested. Snape grudgingly agreed to look into appropriate potions.

"Speaking of potions..." Harry said to his friends with a significant look, to remind them that they had to check up on their brewing polyjuice.

That was all it took.

They were leaving Moaning Myrtle's bathroom, Ron pulled open the door, only to find Snape standing in front of it, looking like an overgrown bat – a menacing, ill-tempered bat, at that. The three friends froze.

"What were you all doing inside a girls' bathroom? An out-of-service girls' bathroom? Care to explain?" asked Snape. They gaped like fish back at him. "Shall I go inside to find out?" he continued in a deceptively calm voice, before any of them had found their voices.

Harry and his friends made unintelligible noises, the panic evident on their faces.

"Or would you care to explain yourselves?" When Snape did not get a quick answer, he walked past them into the bathroom, the adolescents following in his tracks. He did not have to search long to discover their bubbling polyjuice potion. "What in the..." He went as close to the cauldron as he dared, looking into its depths with a sick sort of fascination.

"That's not—" Harry broke off, unsure how to explain.

"That, Potter, doesn't look like any potion you three should be brewing. Not that you should be brewing any potions outside of my class. In fact, if I didn't know it to be impossible, I might think this was..." He trailed off, not finishing the outrageous thought. "No matter. Whatever it is, it won't do any damage once it's gone."

With that, he drew his wand, only to be interrupted by loud, panicky shouts of, "No!" and the three Gryffindors jumping in front of the cauldron.

"Step aside at once," Snape said very carefully, very clearly, his wand still trained behind their backs at the contents of the cauldron.

"We can't give it up, Professor," Hermione said, voice shaky, but determined.

"You don't understand!" said Harry.

"We need it to find out who attacked Ginny!" added Ron. His friends looked at him, worried that he would give out any information at all.

Snape debated his next steps. For a moment, he looked visibly undecided. But they knew, that he must remember a similar situation from the year before. And indeed, Snape slowly lowered his wand.

"You're willing to explain, I take it? Well, come along then."

Harry and his friends followed reluctantly as he led them out of the bathroom and towards the dungeons. They did not speak until they had reached his office, unchanged since Harry's and Ron's visit after their arrival to Hogwarts in the Ford Anglia. Neither boy was happy to see it a second time that year.

Snape got out a vial from one of his many shelves and carefully placed it on the desk. He seemed to debate something with himself, then pointed his wand at the desk to make a pot of tea appear with a pop, together with three mugs. He uncorked the vial and added three drops of the liquid into each mug.

"This is called veritaserum," he began to explain. "It is a potion that will force you to answer questions truthfully. If you think the truth will convince me to let you keep your mysterious potion, then drink this now. Feel free to add the tea, if you prefer," he added with a sardonic smile.

Harry stared at the mugs with dawning horror. "But you could ask us anything..."

"Many secrets, have we? The sort that might land you in trouble, if it became known?"

"You can't do this! There is no way you're allowed to do this!" said Hermione.

Snape's face darkened. "You're right that I cannot force you to drink this. However, there can be no problem with you drinking it voluntarily, of course."

Harry was about to shout that he would never agree to it, when he saw Ron looking at the mugs desperately, his internal fight clearly visible on his face.

"Only if you drink some yourself," Harry said recklessly to Snape.

"Come again?"

"You can ask about the potion, that's fine," Harry said quickly. "But we need a guarantee that you won't just go ahead and – and ask about, er—"

"Things that are none of your business," finished Ron.

"Are you really so delusional as to think that your – silly, childish – secrets can be bartered against mine?" Snape looked outraged.

"Well, there are three of us," said Hermione, going along with Harry's idea.

"And we won't ask anything, unless you start asking us about other things," said Harry, warming up to his impulsive idea.

"What is to stop you?"

"You could expel us for that potion – or at least get us into a lot of trouble," said Ron, a little recklessly.

Harry thought Snape would explode any second, but instead, he summoned one more mug and added three drops to it, making sure they could see exactly what he did. They all took their mugs, added tea and drank. A minute later, four empty mugs were placed back on the desk. Then Snape turned around to light a fire in the fireplace. "Sit," he said curtly, pointing towards the chairs in front of it.

"This dose will be effective for about ten minutes." He checked the time. "You will answer every question as succinctly as possible. You will not ask any questions – not rhetorical ones, not questions to each other, just none. Is that understood?"

Harry was about to nod when he felt a compulsion that was not to be argued with, and ended up forcing out a, "Yes!" His friends did the same. He felt dread creep up on him, tried not to think about Sirius, hoping that his gamble would pay off.

"Good. Now, what is that potion brewing in the bathroom?"

"Polyjuice," came the triple reply once again, though not as simultaneously. Now that he was expecting it, Harry could delay the answer by a smidgen of a moment, just enough to think about the answer, before saying it. The dread lessened ever so slightly.

Snape's lip curled. "You three brewed polyjuice? Tell me—" he went on, but was interrupted by three shouts of "Yes!" He had to regroup at that. Despite himself, he seemed more than a little impressed, and the next few questions that followed all had to do with the potion itself. He found out about Lockhart signing their permission form – which made his lip curl in disgust – and their potions ingredients getting delivered by owl post.

"You say you had most of the ingredients delivered by post. What about the remaining ones?" he then asked.

They all fought the answer, but Harry knew there was no way to avoid answering. "We went to London and bought it from the apothekary in Diagon Alley." That was a truthful answer, even if it was not the whole truth. But the potion let him get away with it. His friends agreed with him, without having to explain more.

"I knew it! I knew you must have left the school when I saw you in front of that statue! How did you even find out about that?" This was asked almost to himself, but the potion did not care.

"Ron's brothers told us about it," Hermione replied quickly, apparently having figured out the same trick as Harry.

"You can't punish them!" said Ron. "That was not a fair question!"

Snape raised an eyebrow at the outburst, but switched the topic. "What I want to know is why you brewed the potion. What are you planning to do with it?"

"We need to question Malfoy. We think he's behind the attacks," said Harry.

Snape drew back, his eyebrows going up. "You are delusional. What makes you think that a second year student could manage something remotely this serious?"

"He might be getting help from his father, who refused to have the school closed," said Hermione.

"He hates muggleborns, he hates us and my family and he's staying at Hogwarts, now of all times!" Ron gave all the safe answers he could think of.

Harry would have loved to point out that the three of them were second years themselves, but the potion got in the way. The inattentiveness cost him. "He hates me. And Dobby warned me that there would be danger to me at Hogwarts this year," he blurted out, then covered his mouth with his hands.

Snape became very still. "Dobby, you say?"

"Yes. He's a house elf – at least that's what he said he was. He tried to keep me from returning to Hogwarts, first by stealing my mail, and then by locking the gate to platform 9¾. And Ron said only really rich families have house elves, like the Malfoys, right?" Harry ended on a question without meaning to.

"Yes, the Malfoys' house elf is called Dobby," answered Snape, and did not even complain that Harry had gone against his rules. They had all grown very quiet, very still, at that revelation.

Snape distractedly asked another few questions about how exactly they intended to question Malfoy, before checking the time. "The potion is about to wear off. You may go now. I will... not... stop you. However, should you get in trouble with another teacher, I will deny having given you anything resembling permission. In fact, I will deny any knowledge of your activities."

With that, he turned towards the desk again and poured himself another tea – in a fresh, newly summoned mug.

The three friends shuffled towards the door. "Er, goodbye, then," Hermione said. "Enjoy your tea." It was not really a question, but the awkwardness of a polite goodbye to Snape made her voice rise at the end.

"I don't," Snape felt compelled to answer. "Not if I don't have biscuits with it." He barely paused to draw breath in between his forced answer and the shouted, "Out!" that followed.

Harry and his friends were already out the door, hurrying back to their dorms, frantically discussing the new information about Dobby and their plans of interrogation.