Over the summer, James has apparently been thinking about something that isn't a method to one day win over Evans, or to not get kicked out of school. Sirius is a little surprised. He's more surprised when James only seems to want to share his new plan with himself and Peter.
It's not difficult for them to find time without Remus around, what with his new job as a Prefect (which they spend so much time teasing him about at first that he threatens them with detention on multiple occasions). James gathers Sirius and Peter in their room, making sure the door is magically locked and no one will be able to eavesdrop before he begins.
Sirius, lying on his bed in the hopes that he'll be able to soak up the last of the autumn sunshine, raises a lazy eyebrow. "Worried a herd of centaurs are going to stampede through, Potter?"
James laughs sarcastically and Peter, still standing in the centre of the room, fidgets a little.
"What's going on?" Sirius asks when the silence has dragged on for too long. "What's so important that Moony couldn't even be involved? As much as he complains, you know he'll be pissed off if you make him miss out on the planning for a prank."
"It's not about a prank," James says and for the first time, he looks a little unsure. "And it's to do with Moony. Moony and his furry little problem."
Sirius lifts himself up onto his elbows. He's not sure he likes where this is going. "What are you planning, Potter?"
Peter looks a little panicked now. Sirius and James don't fight often, but the handful of arguments they've had have ended spectacularly. Sirius can't blame the way Peter eyes the door.
"Nothing like that," James says, a wounded note entering his tone. "It's something that I think might help him. But it's dangerous."
Peter opens his mouth. "More dangerous than-"
Sirius doesn't get to hear which example was about to tumble out of his mouth, because James just looks at him sharply and says, "Yes."
He does look very serious. Sirius frowns. "Alright," he says. "What plan?"
"What if we learnt how to become animagi?" James says, all in a rush.
For a moment, Sirius sits there, stunned. Peter looks between them again and Sirius knows he's trying to interpret the look on his face.
The fact is, it's a genius plan. Of course, they don't know what animals they'll turn into, or how long it might take, or anything else - but Sirius is all for doing anything that could help him help Remus that one time a month he can't touch-
"I'm not sure," Peter says and James makes a quiet sound in the back of his throat.
"You think you can still forge Flitwick's signature?" Sirius asks Peter instead and a grin spreads large across James' face.
Peter looks a little confused, but he nods. He's got surprisingly good penmanship, as they all found out to their advantage in third year. "Why?" he asks.
"If we're doing this, I think we're going to need some books from the Restricted Section," Sirius replies.
It takes a few months.
In and of itself, the magic isn't that complicated - at least not for Sirius or James, who consistently do well in class despite their lack of attention or interest. Peter struggles at first, but with the two others coaching him, he catches on quickly. Keeping everything a secret from Remus is somewhat of a struggle and it becomes exhausting after a while, but Sirius holds on with the knowledge that if they manage this, there's no way Remus will be anything but please.
Well, he hopes.
Sometimes he suspects that McGonagall knows - she's an animagus herself, after all - because she fixes the three of them with knowing looks sometimes, but as with every other suspicion in his life, he assumes that if she did know, she'd say something.
Obviously, the nights when they get the most done are the ones where Remus is out doing Prefect duties and when the moon is full.
December comes and they decide to try it for the first time. It's a full moon and Remus has been looking decidedly out of it all week, so Sirius figures he might not even be back in the dorm tomorrow.
They keep their lights low; even if they're in their room, they don't want to attract attention. James is a bundle of excessive nervous energy. Peter looks vaguely green. Sirius isn't sure what his face is giving away, but his pulse is racing. They're going to try this.
It's a long night and when it's done, Sirius aches all over - and he still hasn't managed it. Disappointment settles low in his stomach.
Peter's not doing any better, though it's not that surprising. He's still having some trouble with the spell and Sirius makes a mental note that they'll have to go through it again.
James' face is paler than Sirius has ever seen it but there's something alight in his dark eyes.
"One more time," he says.
"Not me, mate," Sirius replies. "I'm beat and I'm not getting any closer than I was an hour ago. Pete?"
"Nah, me neither," Peter says.
James grins. "I'm gonna try it one more time."
Sirius shrugs and leans back to watch as James tries the spell again. As with the other times, nothing physically happens - though Sirius figures that, like he, James can see the animal he might become.
Sirius is already excited that he'll get to turn into a dog. He always wanted one growing up, for one thing, and there's another part of his mind that happily points out that dogs and wolves aren't really that far apart, in the grand scheme of things.
He glances up again and feels his jaw drop when he realises - it's working! James is changing!
Sirius clambers to his feet, noticing Peter do the same out of the corner of his eye, and they take a few steps backwards. It turns out to be a good decision, too, because when the stag that James apparently has the power to turn into tosses its head, its antlers cut through the air where they had both been standing a few moments before.
"Merlin's beard," Sirius whispers, entirely in awe of his best friend.
He reaches a hand out and the stag - James - steps forwards, letting Sirius runs his fingers over his head and down his neck. He touches his antlers too, but James trots back out of reach.
Sirius starts laughing. He's still disappointed he hasn't managed it, but this is incredible and now he knows they can do it, it's only a matter of time before he gets it, too. Peter's laughing along with him and there's a few seconds where the stag stands still - and then James is back before them, his grin wide enough to split his face in two.
"You did it!" Sirius exclaims, knowing it's defunct but wanting to say it anyway.
James runs a hand through his hair and laughs with them.
A noise outside of their door has all three of them stopping, though as Sirius exchanges glances with the pair, he knows they're close to giggles.
"When's Moony on Prefect duty?" James asks, when they're sure they're all alone again.
"I think Thursday?" Sirius replies.
James nods. "You'll get it then," he says.
Sirius nods his reply, still smiling. He looks at Peter. "We'll go through the spells with you again, Pete," he says, "And you'll get it too."
They all go to bed with smiles on their faces.
Sure enough, Sirius gets it on the next try and then Peter soon after. His turning into a rat does make James laugh for a solid ten minutes, until Peter points out that his smaller size might have its advantages – for one, if they need to sneak around the castle, a stag is going to be rather conspicuous.
Sirius thinks James pouts for a while after that. He's a little proud of his animagus form, but then, Sirius has to admit, it is pretty damn cool.
They all stay at Hogwarts over the Christmas break and there's a quiet, heated discussion between Sirius and James as to whether they should present their animagus forms as Remus' Christmas present. Sirius says no because he knows Remus will just tell them he'll hurt them and might possibly even turn them in; James says yes because he's mostly being impatient. Sirius wins in the end and all four of them exchange presents like normal, with Remus still none the wiser.
The next full moon is soon after the New Year. Again, in the run up to the moon, Remus looks terribly out of sorts, which Sirius does mention to him.
He laughs. "I know," he says. "It's just-" He looks around. They're in the library. James has gone off to bother Evans somewhere and Sirius thinks Peter has followed him. There aren't that many students in the castle so they have almost the entire library to themselves.
"It's just what?"
"The- It wants to run," Remus says, a note of helplessness in his voice.
"And you-?"
"Well, you know where they put me," Remus replies.
Sirius does. He sneaked out one night to find out, in fact – only to get a terrible telling off from Remus the next day. Still, it's good to know the Shrieking Shack isn't actually haunted.
"It's actually that small inside?" Sirius asks.
Remus hums his agreement, turning back to his Potions essay. "It's fine," he says after a moment, noticing, Sirius presumes, the lack of shift in his expression. "Don't worry about it. School starts again on Monday, so you know I'll be back to normal by then."
He smiles and Sirius smiles back.
The air is fresh – too fresh. There was a rabbit here. He sticks his nose into the grass, inhaling deeply and the stag to his right nudges him with its antlers.
Right, Remus. The plan.
It's difficult to focus, Sirius thinks. He doesn't know how it is for the others, but for him, there's so much to hear. So much to smell.
He hears the rustle of something in the grass and wants to investigate, but Peter-as-a-rat ("Wormtail," James had managed to force out, laughing almost drunkenly after Peter's first transformation) has already darted underneath the Whomping Willow, so he knows there's no time for that.
The tree stops moving and Sirius outstrips even James in his sudden excitement. He slinks down into the tunnel and all of a sudden, down here, all he can smell is Remus.
He's noticed it a couple of times when they've transformed in the dorms, that he can pick up the scents of the other three boys – with James and Peter always taking priority because they've physically been there – but here it's all Remus. This is his place and for a moment Sirius pauses, his ears flattening instinctively.
His human side rears up. No, he can go in. He'll have to be careful with the wolf, but he's a large dog and hopefully, Remus will recognise his scent too.
He trots up the stairs and hears James' tentative steps behind him. He lets his tongue loll out as he thinks about how difficult it's going to be for him with hoofs. He'll have to ask about that in the morning.
The smell is stronger up here. It's almost overwhelming. Sirius sniffs by the door and fights the urge to roll over and whine. Instead, he nudges the door open with his nose-
And he's immediately pinned to the floor by the wolf.
It's holding its teeth at his neck and Sirius lets the canine instincts he's been fighting take over. He can smell James' panic from here and Merlin only knows where Pete's wandered off to.
He lets out a little whine and the wolf pulls its head back, sniffing the air. It's Remus, Sirius reminds himself, though those yellow eyes are nothing like the soft brown of his friend.
There's another huff of his air to his left – it's James, his head lowered threateningly. Remus-the-wolf eyes him warily. Then he lifts off Sirius entirely and pads back into the room with a low growl.
Sirius bounces to his feet and shoots James a look. His tail is wagging. Inside, the wolf paces but when they enter, he doesn't attack.
Sirius is totally counting that as a win.
When Sirius wakes up sometime in the early afternoon, he winces at the sunlight streaming directly into his face.
"What time is it?" he mutters into his pillow.
He hears a grunt from James' bed.
"Wormtail!" Sirius shouts.
Peter lets out a startled squeak.
"Time?" Sirius asks.
"It's two in the afternoon," says another voice, sounding dryly amused.
Sirius blinks a couple of times and sits up. Remus is sitting on his bed, looking better than he has all week.
James is fumbling around for his glasses. Sirius doesn't know about the other two, but he aches all over. It's not quite like having a hangover, but it's not far off.
"Alright, Moony?" James asks.
Remus hums, fixing each of them with a look. "Mind telling me what happened last night?" he asks.
Sirius raises his eyebrows. Well, straight to the point then.
"What do you mean?" James asks, ever evasive.
"What happened?" Remus asks. His expression falters suddenly. "Did anything happen? I mean-"
James laughs, throwing back his duvet and taking a few wobbly steps. So, he's aching at least. Sirius smirks.
"You have to promise not to be mad with us," Sirius says before James does anything.
Remus frowns. "I'm not promising that."
"Then you promise to listen to our explanation before you get mad?" James asks.
Remus nods. He looks unsettled. Sirius doesn't blame him.
"You first, Pete," James says, grinning.
Peter groans but does as he's told – and Sirius thinks it's as much a testament to his and James' work as it is Peter's determination, the ease at which their friend transforms now.
Remus frowns, standing when he sees the rat on the floor. The expression on his face is changing from one of trepidation to horror. "You didn't…?"
James doesn't let his grin slip – and when he transforms into the stag, Remus lets out an audible gasp. Sirius fights the urge to roll his eyes. Of course.
When he looks back, Remus is staring directly at him. "Well, go on then," he says.
"What, Moony, not mad?"
"I said I'd reserve judgement." His smile turns a little devilish. "Unless you couldn't do it…?"
Sirius frowns and throws back his own duvet, transforming into the dog before his feet even touch the floor. He bounds over to Remus, his tail wagging hard and lets out a contented whine when Remus buries his hands in his fur.
He looks up and Remus' eyes are noticeably wet. "I remember you," he says quietly. He rubs a hand over his face. His voice trembles when he looks at all three of them and says, "Thank you," and Sirius lets his tail keep wagging because this is honestly the happiest he's ever felt.