Lily was dozing in the common room when she was woken by footsteps and a familiar voice whispering, very angrily "Wormtail!"

Peter's voice quickly replied with an abashed "Sorry, Sorry!" Lily blinked. Were those idiots sneaking out after lights out again? She sat up, ready to confront them.

There was nothing there. She looked around for a moment in confusion, before deciding that the idiots must have just been giving her nightmares. She yawned, stretched, picked up her book, and headed up the stairs to the dormitory.

As she reached the third stair, she heard it again.

"Oh. Wow. Evans gets hotter every time I see her." It was Potter's voice, and she froze.

"Shut up, Prongs, the cloak won't stop her hearing us." That was Sirius, she registered, but it seemed unimportant in comparison to what he'd just said.

Cloak.

She wasn't hearing things. They had an invisibility cloak! No wonder they got away with so much mischief. She tiptoed down just in time to see an invisible hand open the portrait hole and step out.
Lily was thankful that she'd mastered the disillusionment charm, quickly casting it on herself and following the voices. It wasn't hard: Sirius and James seemed to be arguing about something, while poor Peter begged them in whispers to be quiet. She couldn't help thinking she was glad Remus wasn't there. He was the nicest of the Marauders, so she would have been less keen to get him in trouble.

Technically, Lily knew she should have stopped them the instant they left the Common room, but she hadn't. She wanted to catch them doing something really bad, like enchanting Mcgonagall's chair to giggle when she spoke or something.

"No, Sirius, I will not date one of your exes!"James snapped, at a higher volume. "I'm a one-woman man." Lily frowned. She didn't know Potter was dating anyone. Hadn't he been flirting with her at dinner like always? Clearly she'd been right to think he'd just done it to annoy her.
"Oh please." Sirius' voice dripped with scorn. "Evans hates you."

She almost stopped still in her tracks. Potter was talking about her? He was refusing to date anyone else because of her?

For a moment she almost felt warmed by the idea, before she remembered it was Potter she was thinking about. Urrgh. No, he was after her because she was the only one who'd ever turned him down.

Realizing they'd kept moving, Lily moved to catch up. She didn't hear any more of tohat they were saying, but they were loud enough that it wasn't too hard to follow them. Once they got outside, (though Lily had no idea what they were going outside for: A prank in the greenhouse perhaps?No, wrong direction) it was quite easy to see their footprints in the muddy ground, particurlarly as the full moon was very bright above. it was a chilly night, and she couldn't help but shiver. She was beginning to regret not calling them out when there was a teacher nearby to help. Not that she couldn't handle them herself, it just would have been nice to have some backup. And not be standing around in the cold.

It felt like she was following them forever when she saw dark shapes appear to the left of where she'd thought they'd been, but not human shapes. Animals: A huge thing that was either a bear or a dog, and some kind of...deer? She wasn't sure, but a moment later the animals vanished. So did all the sounds coming from Potter and his mates.

it didn't take long to figure out that they must have transfigured something nearby to look like those creatures while they snuck away in the cloak. The must have noticed her following them and done this to lose her. Well, if she just waited and listened she was sure to find them. They had to be waiting close by, being as quiet as possible, and there was no way they could keep it up forever.

She could out-wait them. They were not getting away after she'd trailed them out into the freezing cold in the middle of the night!

She folded her arms and waited. And waited. Then she moved back quickly.

She'd been standing by the Whomping Willow! She had no idea why it hadn't been moving before, but one of its limbs had nearly impaled her. The assualt only lasted for about ten seconds before the tree miraculously froze again.
Lily didn't feel relieved for long. From the tree she could see those animals again, but this time they were accompanied by another huge beast. She froze. Something about it rang alarm bells in her mind.

A wolf? What was a wolf doing on Hogwart's ground? And a deer?

But wolves rarely attacked humans, she knew that, and it couldn't be hungry or it would be eating the deer, so she didn't run. She just watched in wonder.

Then, too quickly for her to react, the wolf turned and leapt for her. She struggled, trying to aim her wand, but it fell from her hand as the wolf's teeth sank into her shoulder. She let out a horrifying pain was terrible, worse than anything else she'd ever known. Rational thought was driven from her mind and all she could do was struggle helplessly beneath the wolf.

Her eyes focused on the full moon above, and it was the last thing she saw before the wolf sunk it's teeth into her abdomen and she blacked out.

They hadn't known anything was wrong until they heard ily's scream. It was horrifying. Without a thought, Prongs and Padfoot leapt for Moony,trying to pull him back. James' heart broke the instant he realised who it was. He realised what must have happened immediately. Evans had followed them out.

Padfoot pulled Moony away for an instant, but not long enough. Lily moved, and Moony leapt back to sink his teeth into her again.

Fear forced Prongs into action. He leapt over Moony, trying to push him away and get between the wolf and Lily. Wormtail was the one who managed to get Moony to move, biting on his tail till he howled and turned. Padfoot wasted no time, pushing Moony back down the tunnel.

The instant they were gone, James transformed. He didn't even know what to do. Her wounds looked terrible, jagged and raw. His stomach lurched but he managed to force himself not to throw up. He sent up a shower of sparks, hoping the teachers kept an eye out on full moon nights, and summoned some dittany. He applied it to Lily's wounds as quickly as possible, hoping it would stop the bleeding. He was scared to move her, terrified he'd do more damage. He tried to press down on the wounds to stop the bleeding and just waited, desperately hoping someone would come.

It wasn't unusual for Madam Pomfrey to stay up all night on full moon nights, unable to sleep as she worried that this would be the month when something would go wrong. She always worried that in the morning, she would find a dead boy on the floor rather than just an injured one.

She was staring at the window, waiting for morning to come, when her heart jumped into her throat. Someone was shooting up red sparks from right by the Whomping Willow.

She wasted no time in grabbing emergency supplies and racing down there. She didn't know what to expect. She was the only adult in Hogwarts who knew (or suspected-they hadn't ever told her in so many words) what the other Marauders did on full moon nights. Either Remus was injured and they were desperate, or the Wolf had turned on one of them. Maybe Peter, his seemed like the most vulnerable form. She didn't waste any time pondering it, she just raced down at top speed taking every shortcut she knew. She inwardly cursed the inability to apparate inside Hogwarts.

It didn't take long before she was racing towards two figures on the grass by the light of her wand. James Potter scrambled out of the way as soon as he saw her.

"Madam Pomfrey, you're here, Remus bit her, she followed us, I gave her dittany but I didn't know what else-"

James was nearly hysterical, she noted, but there was no time to deal with that. Her hearrt sank as she viewed the wounds. Lily Evans might not make it through the night, she thought, something inside her twisting painfully.
When she spoke, it was in a calm authoritive voice.

"James, fetch Mcgonagall, Dumbledore and Slughorn. There are some potions that might help. Hurry! Send them to the hospital wing."

He nodded and raced off at top speed as Madam Pomfrey cast a long littany of spells to try and heal the wounds. Eventually the bleeding stopped, and Pomfrey conjured a stretcher to carry her back to the castle.

When she reached the Hospital wing, James was already there with the teachers she'd asked for. At the sight of Lily's blood covered body, Slughorn and McGonagall both paled and Slughorn sank down into a chair. James whitened, shaking considerably, and vanished into the adjoining bathroom. They all tried to ignore the sound of him throwing up. Slughorn was turning quite green by this point, and Pomfrey suspected he might be joining Potter shortly.
"Horace, could you please summon all potions that might help heal werewolf bite wounds. Minerva, Headmaster, could you please help me perform the necessary spells."

They nodded, and a flock of vials flew in as Slughorn waved his wand. Pomfrey moved over to let Dumbledore and McGonagall have a better view of the wounds. This also gave Slughorn a clearer view, and he raced into the bathroom almost immediately.

They worked tirelessly to heal Lily's wounds throughout the remainder of the night. As the moon set, all Pomfrey wanted to do was sink into bed and sleep.
She knew she couldn't. Miss Evans was stable, but she had another patient to attend to.

A/N- I'm trying to go by the book description of werewolves as being very similar to real wolves, rather than what Lupin looked like in the film. Also something appears to have caused double spacing and parts of the chapter to be in bold when uploaded. Please forgive that, hopefully I'll manage to fix it soon. Thank you! :)