Severus gulped. The four Marauders were notorious. They were irresistible to girls (with the exception of Peter), the most hilarious and ingenious pranksters, scourge of the professors and that morning, as Severus 'Snivellus' Snape had practised his new spells, they were striving to become animagi.

Their motive was Remus. Poor Remus had been a werewolf for as long as they had known him, and every full moon the three others watched with sad eyes as he left their dormitory for the Shrieking shack. There, they knew, he would wait until agony consumed him, and he became a creature of the night, claws splitting out from his fingers, fur sprouting on his back, but his eyes – they remained almost human, squinted as waves of white pain racked his body.

It was Sirius and James who came up with the idea – of course it was not dim-witted Peter – to accompany Remus as animals themselves. But it had been Peter, so desperate to please, who had spent the time in the library researching and finally discovering the possibility of animagi. Sirius and James were pleasantly surprised, and set about working out the process. In the end, most of the thinking was theirs.

First the boys had to discover the form they would take, so that they could accurately envisage the animal in order to become it. James, idly transfiguring a pencil one afternoon, had, in some way he could barely explain, conjured up a huge stag. It wasn't deliberate, and that was how he knew the stag was exactly what he wanted to be as an animagus. Sirius had done it next, with a pebble, eventually creating the large black dog with calculating eyes. He fell in love with the dog, somehow it reminded him of himself, but different. He knew he would become the dog. Peter managed it last. While James chose the stag because it had come of its own accord, and Sirius the dog because he was fascinated by it, Peter was forced to become a rat as that was all he could manage. Sirius and James had a hard time hiding their amusement at this.

That day they were ready to attempt the final stage. They brought out the objects that had provided their animals – for James a pencil, for Sirius a pebble and for Peter a lump of clay – and transfigured them into the full size animals. Then they had to look into the animals eyes and imagine that they were the animals, get inside their heads. When they did this, the two bodies would merge and the boys would take their animal forms for the first time. They were just about to begin this process, Remus watching with amused curiosity from where he was leaning on the lichen-laden tree, when Remus hissed in alarm. ''Someone's coming,'' he whispered, ''hide those animals!''

With casual flicks of their wands, Sirius and James returned the animals to the innocent items they really were. Peter, in his alarm, was not quick enough and Sirius, not bothering to contain a frustrated sigh, did it for him. Then they all put away their wands, Remus opened his copy of The Uses of Fire Crab Fuel in Potions and Other Media and Sirius and James started to talk nonchalantly. This was how that sly Snivellus found them.

Severus turned to run at the sight of them. He wanted no trouble, he was just innocently – well, perhaps not innocently – practicing some of the spells of his own invention, he wasn't asking for the beating he was sure to get. Soon enough, all of the Marauders were chasing him with joyous laughter as he sprinted round the lake. However, Severus was tired and his weak legs failed him. In retrospect, he should have used summus sum but his mind was blank with dread. Or callidus sum, that would have prevented the blankness.

As he passed the great flank of the Forbidden Forest he heard a whistling and felt a heat at the back of his neck. A spell! Before he could shout a counter curse he was lifted off his feet and dangled upside down, a metre in the air. Levicorpus, James' favourite. Sirius cast stupefy, the golden ball flew towards Severus, who whipped out his wand and brought up a shield just in time. Sirius lined up another spell and in desperation Severus fired a sectemsempra at each Marauder. Chuckling, each of them dispelled his attempt, even Peter. ''That's a pretty nasty curse you've got there, Snivellus,'' laughed James.

''It's a shame you can't put any power into it,'' Sirius joined.

''Leave me alone!''

''Why would we do that, Snivellus?''

''And don't call me Snivellus,'' he muttered, before firing the stupefy he'd been charging up behind his back. Golden orbs spat out in the direction of the Marauders. Sirius, James and Remus dodged them, but Peter was less fortunate, taking three in the chest and passing out on the spot.

''Risky, Snivellus,''

''You still have some lessons to learn,''

''What do you think, James?'' This was Sirius, ''Expelliarmus or my new hex?''

''Hmm… Let's treat Snivellus to that hex this time, eh? Oh wait, I have a better idea!''

''Both!'' They said in unison.

And so Severus felt his wand fly out of his hand, and soon after the hex hit him he began to cough uncontrollably, before his lunch made an unwelcome appearance. Sirius held out his wand, wanting to maintain the effects for as long as possible. I will kill you all, thought Severus, every one of you, and you will each die a new and excruciating way!

Just as the last of Severus' stomach juices slipped to the ground (he was still upside down at this point), the boys heard a sudden furious scream. James turned and saw a flash of fiery red hair and glinting green eyes as none other than Lily Evans stormed towards the Marauders, her face thunderous. James felt a sudden weight in the pit of his stomach, like it was full of lead.

''WHAT, Potter, do you think you are DOING?''

''Lily…'' bleated Severus.

''Shut up, Snivellus,'' spat Sirius, who did not care half as much as James about Lily's approval.

''Oh Merlin, here we go again,'' sighed Remus, who glanced at Peter balefully.

Peter merely whimpered in fear.

''Uh, uh Lily… I, uh… Err…'' James stuttered, clearly in some distress.

''How DARE you abuse Severus like that!'' she screeched, releasing him from his hex with a flick of her wand. James cut off his levicorpus and Severus tumbled to the ground, trembling.

''I… It's just a bit of fun, Lil…''

''A bit of fun?! A bit of FUN?! You think Severus was enjoying himself?''

There was a pause as James went as red as Lily's hair and looked down to his shoes. ''No, Lily.'' Honestly, Sirius thought, couldn't James see that she acted as though she was a headmistress and he a naughty pupil? But no, James was far too smitten to see any flaws in Lily.

Huffing, Lily went over to Severus and helped him up. ''And to think, Potter, that you expect me to love you! What can be going through that thick skull of yours?''

''Lily, please-''

''And don't call me Lily! You can call me Lily when I like you, which I never will!''

''What would you prefer? Sweetheart?'' offered Sirius.

''You're just as bad, Black! As far as all of you are concerned, I'm Evans if you talk to me. But I will never talk to you again!'' she hissed, and with that, led Severus back towards the castle.

Sirius, Remus and Peter looked at James patiently, expectantly. ''Come on guys,'' he sighed, finally, ''I don't feel like working on the animagi today.'' Silently, the four friends wound their way up to Hogwarts, slowly so that they didn't have to confront Lily and Snivellus again.