Summary: There was a line. A painfully thin line, between man and beast. And if you went too far across it, you couldn't go back. Remus knew this. Looking back … there were two specific moments in his life, where the rage of the wolf had almost got the better of him.

Not your average Remus fic. But then, if Harry has a right to smash a few things when he's pissed off at the world, then you can bet Remus has that right as well. I mean, he's a werewolf! What more reason do you need? Think about Fenrir Greyback – being a werewolf isn't just for the full moon …

Disclaimer: All characters are the exclusive property of JK Rowling's imagination.

Rage of the Wolf

There was a line. A painfully thin line. It lay between what was right and what, if he lost sight of the line, would surely kill him. It was the boundary between reason and violence, between conscious and unconscious, between man and beast.

The line was so thin as to be nearly transparent. He had to be so careful – he always had been, always had to be. He was good at finding the line and keeping his eye on it at all times. That was his rule. One eye on the line. Because once you crossed it, once you let it take over, it was the hardest thing in the world to go back. And if you couldn't go back, then you were lost forever.

One eye on the line. Yes, that was the way. When he felt his resolve being tested, that was all he had to remember. And it worked, it really did. It did. It worked. As long as he remembered, as long as he kept that eye open, as long as he constantly reminded himself what was at stake.

Of course, there were times … he'd come dangerously close. Looking back, he was sometimes amazed at his own self-control. Looking back – looking back, he knew that there had been times it had nearly gotten the better of him, times when he had allowed it to bubble to the surface; that secret rage, the wolf within …

1975 – Fourteen hours after the Full Moon.

Betrayal. Anguish. Rage.

Mostly, betrayal.

Sirius stood at the door to the dormitory. Remus didn't know when he had picked up his wand, but it was now pointed directly at his former friend's heart.

'I'd leave if I was you,' he said quietly. It didn't even sound like his voice. It was as though something had taken over. It was like transforming, but he could see himself in his transformed state from some point outside his body.

There was no turning back. The part outside his body was egging him on. Blood was rushing in his ears. His face was hot, his limbs trembling with fury. A few sparks left the end of his wand.

Sirius stared. He looked at a loss for words.

James grabbed Remus's arm and tried to catch his eye.

'Moony! Calm down, mate! Don't do anything stupid, all right?'

But Remus was beyond reason.

'Stupid? I'm not going to do anything stupid. If you want someone to do something stupid, you'll have to talk to Sirius.'

Sirius glared at him.

'Look, pal, I said I was sorry; what more do you want?'

Remus shook James off and advanced towards Sirius, who stood his ground defiantly.

'I don't want anything from you, do you understand! Nothing! Nothing you could say would make this all right, you scheming bastard! I thought you were my friend, but you just used me like something you bought from Zonko's! Well, enough! I've had it! I want nothing to do with you!'

There was a ringing silence. Sirius and Remus stood two feet apart, Remus still clenching his wand. Sirius continued to glare through his dark eyes.

'It was just a joke, Moony. Lighten up.'

'Sirius!' James warned. But Remus didn't even hear him. Rage coursed through his muscles, giving them strength. Sirius was normally a lot stronger than he was, but perhaps Remus had managed to catch him off guard because within a second he had him pinned against the closed dormitory door, his wand at the throat of his onetime friend.

'Remus!' James yelled, jumping forward, trying to pull them apart. But anger had tapped into power Remus hadn't even known he'd had, and he was able to push James off with one hand.

'Go away, James!'

'Come on, Remus, don't do this! This isn't like you!'

'I think it is,' Remus growled through clenched teeth, staring straight into Sirius's grey eyes. Sirius scowled back.

'What're you going to do, Prefect boy? Going to curse me?'

'You're awfully cocky for someone with his back up against the wall,' Remus retorted, his wand sparking as he fought to control the urge to rise to Sirius's bait.

'You don't have the balls to do it – let's just face it,' Sirius pressed. 'You would have done it already. You would have done it as soon as I had walked into the room.'

Remus leaned forward, his forearm pressing into Sirius's neck. Sirius gasped for breath.

James lunged forward again, this time managing to wrestle Remus away. Remus fought as Sirius stood at the door, rubbing his neck.

'Let GO, James!' Remus yelled, desperately trying to free himself from James's grip so that he could fling himself at Sirius and beat him into a bloody pulp. 'Just let me go!' James stubbornly remained in his way.

'Sirius, get lost, will you?' James said loudly. 'You're only making this worse.'

Sirius scowled. 'Yeah, I'm out of here,' he muttered, wrinkling his nose as he watched Remus struggle to get at him. 'Tell me when he's regained his senses, will you?'

Remus struggled harder, but James now had a firm hold and wasn't about to let go.

'Just get the hell out of here, you git!'

Sirius muttered something indistinct before leaving, slamming the door behind him. Only then did James let Remus go. Remus ran to the door and grabbed the handle. It wouldn't open. He tried again.

Stuck tight.

'Best if you cool down for a bit, Moony,' James said quietly.

Remus turned around. James's wand was pointed at the door handle.

'Why'd you stop me? Do you think I can't take him? Do you think I don't deserve to?'

James sighed and went back to his bed, where he sat down. He sent Remus a concerned look.

'I just don't want you to do anything you'll regret, Remus,' he said.

'REGRET?' Remus exploded. 'You don't want me to do anything I'll regret, is that it? Right now my only regret is that I didn't curse him on sight! He sold me out for a prank! Do you really think I'll regret cursing the bastard?'

'Yes, Remus. I do. And I think you know that I'm right. He did something terrible – none of us are denying that. And he shouldn't have sold you out, that's true. But at the end of the day he's still your friend. This isn't like you, Remus. I'd hate for you to do something while you were like this and hate yourself for it later.'

'Oh, and you know what I'm like?' Remus yelled, still not ready to give up. 'How do you know this isn't exactly what I'm like? You don't have all the answers, James, no matter how much you think you do! I've got every right to be angry! Damn it, James – don't you defend him to me, you're just wasting your breath!'

He was pacing the room now. James watched him uneasily.

'Remus, please. We're all mates here.'

'Not him. Not anymore.'

James sighed heavily. 'You can't believe that, Remus,' he said quietly, almost to himself. 'You just can't.'

Something in his voice made Remus stop and take notice. He frowned at his friend as though seeing him for the first time. This was James who sat before him, begging him not to do anything rash. James Potter. Prongs. Telling Remus not to do anything he'd regret.

'Bit of a switch, this,' he noted. His anger felt as though it were being drained out of him by some invisible force. He let it go – at least, he let most of it go. He held on to a small bit, a bit he didn't think he would ever be able to forget about.

James smiled weakly. For the first time, Remus noted that his friend – yes, James would always be his friend – looked thoroughly miserable. What did he have to be miserable about?

'Listen, Moony,' he said quietly, serious for once in his life. 'You can be angry at him all you want, ok? I understand that. Hell, I'd be angry at him too – I am angry at him. But if it were me … if it were me right now, in your shoes …' he sighed. 'If it were me, you'd be right here, reminding me that Sirius Black, despite his faults, is my best friend, and yours. You'd say that no matter how much of an arse he is, he's also loyal and caring and above all our mate, which means that we have to stick by him because we both know that he'd stick by us. That's what you'd say, Moony. You know it is.'

Remus stared at him. He shivered as he realised what he had almost done in a fit of anger. He would have cursed his friend. One of the few people in the world he had trusted with his secret. And despite all that had happened …

Remus would have trusted him again. Because that's what you had friends for.

James was watching him concernedly.

'I know you're angry at him, Remus,' he continued. 'And don't get me wrong, you have every right to be. I'm going to stick by you, mate, trust me on this. I can't forgive him unless you do. But, as your friend, I just have one small favour to ask.

'Don't take your time forgiving him. I know you and Sirius have never seen eye to eye, but I'm afraid that I'm lost without him. He's my best mate, the brother I never had. All you guys are my brothers, and the thing with family is that it's a lot more of an effort to keep up being angry than it is to just get along. I can't forgive him until you do, Remus. I won't, for your sake. But I'm asking you not to drag it out too long, for the purposes of my own sanity – and Sirius's too, I suspect.'

Remus sighed.

'You're a good friend, James,' he said finally, after a long pause. 'Where'd you come up with all that stuff?'

James grinned. 'When it comes to uncanny insights, I learned from the best, Moony.' Their eyes caught. Remus smiled in spite of himself.

'Me?'

'You bet.'

Remus laughed. It was easy to talk to James. It always had been. James made life look easy, and the more one talked to him, the more one was convinced of the fact. Remus had never met anyone who had James's knack for simplifying the world. He sat down next to James on the bed.

There was a silence, a friendly one.

'Not yet, but soon,' Remus said finally, avoiding James's eyes.

James nodded. 'That's all I'm asking.'

There was another pause.

'James, about before …'

'Don't talk about it. You'd do the same for me.'

'I meant when you stopped me from killing him.'

'So did I, Moony. So did I.'

1981 – A week before the Full Moon.

Betrayal. Anguish. Rage.

And this time, grief.

This time, there was no James to talk him down. This time …

He sent a curse into an unoffending doorframe. It felt good to watch the wood splinter and disintegrate. He did it again.

He'd seen people laugh maniacally at moments like this, but there was no laughter in him now. There was nothing. Nothing except the rage, and the grief, and the pain … the pain that would never end, that was more excruciating than a thousand full moons.

They said that werewolves could endure more pain than other mere humans. But they had been talking about physical pain, not the kind that tore you limb from limb and left you standing to defend yourself. The kind of pain that did not leave a mark, but stole every breath from your lungs and left you gasping for air. The kind of pain that you felt with every beat of your broken heart.

For the first time in his life Remus wished that it was the full moon. As a wolf, he could run, he could chase down small creatures and let his rage loose on them, and he could howl at the full moon and blame it for his troubles …

Yes, the full moon would have come as something of a comfort. It would have been a release, an escape. Wolves didn't lament the loss of their friends. Wolves didn't have to live with the grief or the guilt. Wolves didn't betray each other, either, come to that, and wolves most certainly did not lie. Animals didn't know how to lie.

With a yell, Remus destroyed a chair with a sweep of his wand. Splinters flew in all directions. Oh, how he wished it could be Padfoot's head! How good would it feel to have him here, right now … to look into his eyes and have him know that Moony had been his end, to have him know that James and Lily's lives – not to mention Peter's – would not go unavenged?

Such a job should not be left to the Ministry. It was too personal, too close to his heart to be left to government officials. It should be dealt with passion and fire and above all, it should be drawn out and painful. Yes. He should not be able to destroy everyone Remus loved and then get away with a mere prison sentence. He should be made to suffer, just as he had made Remus suffer.

A minute or so later he sat on the floor, tears obscuring his view of the destruction he had let loose on the room. The furniture was in shards – it had been mostly second-hand anyway, near to falling apart. The doors and kitchen counter bore the deep marks of rogue curses. There was blood on the doorframe from a sudden and desperate need he'd had to tear something apart with his bare hands.

This had been, in a strange way, the thing to bring him back to his senses. As he sat on the linoleum, his fingers in his mouth to stem the flow of blood, he bit down hard, trying to stop a sob from escaping, trying as best he could to distract himself from the pain.

As his anger drained again, and his strength faded, he was left with only a vast and empty sadness.

He wished that Sirius had at least had the decency to finish him off, too, instead of leaving him with nothing.

Tonight, no one had been there to talk him down. James would never again be there to simplify the world.

Remus wept for his lost friends, all four of them.