A/N A few characters who have left the show are in this story. 5x03 spoilers.

Stiles Stilinski never realized what powers he had until the day Tracy Stewart died.

The night before would be considered crazy if Stiles and the McCall pack didn't live in Beacon Hills. After a teenager named Donovan threatened Stiles' father's life, him, his lawyer, and a couple cops were attacked by Tracy Stewart - a girl with night terrors and the most current experiment for the so-called Dread Doctors. She brutally injured two cops and murdered her father.

The next day started out like any other day for Stiles - waking up, going to school, and hoping he and his pack will survive another day. "Dude, there's nothing wrong with the guy. You have to learn to trust people," his best friend, Scott, tells him as they walk to class.

"Scott, I was right about Peter. And Matt, for that matter. Others too," he replies, stopping and turning to face Scott. "There's something off about him. I don't buy the whole story about him becoming a werewolf either."

Scott rolls his eyes. "Why can't you trust anyone?"

Stiles sighs as he bites the inside of his mouth, clearly annoyed. "You asked me this last night, and the answer is still the same: Because it's impossible for you to not trust anyone."

"There's hope for everyone."

"Yeah, well, if there was hope for everyone, then Allison would still be alive. Peter wouldn't be locked away in the Eichen House because he's a psychotic killer. Kate would've killed herself instead of harboring an armor or crazy ass beserkers. Aiden, Erica, and Boyd wouldn't have died. This place is the world capital of homicides. There's not a lot of hope left."

Something flickers in Scott's eyes as he talks about Allison. He noticed that Scott would always pretend that he was okay with the girl he loved dying in his arms, but Stiles knew the truth. "Sorry, man."

Scott shakes his head. "It's fine. See you later."

***

Stiles sat in Economics, listening to Coach Finstock go on about a topic he could care less about. He tapped his pencil on the edge of his desk, droning out, staring at the back of Danny's head. Stiles was still upset that Danny didn't find him attractive. At the least drag queens he met a few years ago were into him.

Isaac turned towards Stiles. "Stiles," he hisses.

Stiles sighs. Oh, joy, he thought. It's unhelpful scarf boy. Stiles particularly hated it when Isaac Lahey talked. Sure, he was in the pack, and they have a love-hate relationship, but that didn't change how unhelpful and unnecessarily witty Isaac was.

"What?" Stiles replies, looking down to see that his pencil had a coating of spiderweb on it. His eyebrows creased in confusion. The same thing had happened a few nights before - spiderwebs appearing out of no where.

Isaac juts his head towards the door. "Liam wants us. He says that Tracy's here."

"Stilinski, Lahey, want to share your conversation with the class?" Coach says, raising his eyebrows and pointing in their direction.

"We'd love to," Stiles says. "We were just planning a murder, you know. The usual. Talking about where we're gonna hide the body."

Isaac smirks. Maybe one of the reasons Stiles didn't enjoy Isaac's company was because they were both so sarcastic. "Do you think the refrigerator in my basement will be good?"

"I'm not sure," Stiles replies. "Maybe the broken ambulance at the hospital?"

"Stilinski, Lahey, words can't describe how you two much you make me want to strangle someone. Preferably myself," Coach says, rolling his eyes. He goes back to teaching when Isaac stands up, and grabs Stiles's arm, pulling him up.

"What are you two doing now?" Coach asks, groaning audibly.

Stiles stammers, "Family emergency."

A voice that belongs to Liam erupts in Stiles' ears. "C'mon, guys, we're gonna need some help."

His hand immediately goes to his ear. He shouldn't be able to hear that. It was a werewolf ability. Stiles looks around at everyone else, but they're all just staring at him and Isaac. "You two aren't related," Coach yells at them as they walk out the door.

Isaac smirks, shrugging his shoulders. "How would you know that?"

Coach opens his mouth to reply, to yell at them, most likely, but they're already out the door. Liam sighs, with Scott, Kira, Malia, and Lydia by his side. "Took you long enough," he mumbles.

"You couldn't have just waited 'till class was over, huh, Liam?" Stiles says.

Lydia looks at him, her vibrant green eyes sparkling. Stiles may be dating Malia, but that never changed how much he loved to look into her beautiful eyes. "A girl who murdered two people last night is here, and you want to stay in Economics?"

Stiles shrugs. "I don't know, maybe we'd be lucky enough to see her kill Coach."

Lydia stifles a laugh, and Scott says, "Amen to that."

"Where's Jackson?" Kira asks.

"Nobody likes Jackson, we don't need him," Malia says.

They all laugh, but Scott interrupts their moment of happiness by saying, "No, for real. Have any of you guys talked to Jackson today?"

A chorus of 'no's erupt. "I agree with Malia, we don't need him," Isaac says as they all walk towards the classroom Tracy was supposedly in. There was a small window on the door and, somehow, Stiles' vision focused, and he could make out every little detail about Tracy. Her messy dark brown hair swung over her face, and her eyes gleamed yellow. Although it wasn't a normal yellow, it seemed more vibrant and even a bit green. Fangs protruded out of her mouth, and claws out of her hands. She was holding the desk strongly and almost violently as the table snapped in half. Her feet were bare, and had strange, green-brown veins sticking out of them.

"That's not good," Scott mutters. Stiles shook his head to get rid of the unusually sharp image in his mind. When he opened his golden brown eyes again, he could only tell that it was Tracy, and nothing else.

This is so damn weird, he thought as Isaac pushed him and Scott out of the way, and told every one to stay back. Lydia opens her mouth to protest, but Isaac gives her a sharp look. We all back away. Why are we listening to him, since when does Isaac make any good plans? Stiles thinks.

Isaac opens the door. "Tracy," he says.

"Oh, god," Stiles mumbles, throwing his hands up in the air.

"Mr. Lahey, is there a reason you're interrupting my class?" Mr. Yukimura says.

"Yes, yes there is," he says, and Stiles knew that Isaac just gave him the 'some weird supernatural shit is about to go down' look. Mr. Yukimura nods, and turns towards Tracy. "Ms. Stewart, I think Mr. Lahey wants to see you," Mr. Yukimura says.

Tracy looks up, and her eyes stopped gleaming. Good, Stiles thought. Don't need the whole world knowing about her.

Tracy stands up, and walks towards Isaac. Her eyes looked like empty, like they were currently visiting another universe. She stumbled, and Isaac grabbed her arm, walking her outside, and mouthing a 'thanks' to Mr. Yukimura.

Tracy stumbled out of the classroom, and she grabbed Isaac's wrist. He winces in pain as blood begins to ooze from where she's holding him. He yanks his hand off of her as she falls against the wall, and three wounds from her claws begin to heal. "Should we take her somewhere?" Kira asks.

Scott suggests, "Deaton's?"

Malia rolls her eyes. "Remind me again why we're helping a killer."

"This is what we do Malia. We save people. She's probably not in control," Scott says. But before Malia can say something about killing her, Tracy says, her voice empty and emotionless, "They're coming. They're coming for all of us."

Then she collapses to the floor, and a silver substance flows from her mouth.

***

Scott, Malia, Isaac, Deaton, and Stiles help place Tracy on the operating desk in the veterinarian's office.

"She seems to be unconsious, nothing bad," Deaton begins, and touches the silver substance on the corner of her lips. "Now, this silver liquid, is something I've never seen."

"What do you think it means?" Isaac asks, leaning against the wall. "And, what if she tries to attack us?"

"Ah, thanks for reminding me Isaac," Deaton says, and grabs a vile of black dust. Mountain ash, Stiles thinks. Deaton opens the bottle, and throws it up into the air, spreading a circle around them.

"That's not gonna help! Now we'll be trapped in here," Isaac says.

"He has a point," Stiles says. Even though he'll be able to get out, Scott, Isaac, Malia, and Tracy won't be able to get out. And he didn't want to see his best friend, girlfriend, and the scarf boy he has a love-hate relationship with to get torn to pieces by a psychotic werewolf.

Malia puts her hand out, and the forcefield of the mountain ash appears. "Weird," she says, jumping back a little.

"Stiles, can you hand me that knife?" Deaton says. Luckily, everyone was turned in a different direction when Stiles did this:

Stiles looked over at the knife, and stepped forwards to get it. But, a spiderweb shot out of his hand, sucked onto the knife, and it soared over to him. Stiles jumps up, confused and little bit frightened by what he just did. He hands the knife to Deaton, who doesn't seem fazed by the fresh coat of web on the handle. He just takes the knife and presses it against her arm, dragging it across until - CRACK! The blade broke right off. Deaton's eyebrows creased in confusion.

He put the knife away as he touched her neck, where, for just a second, Stiles saw something move. "Malia, help me flip him over. Something in her back was moving up and down, back and forth. Then something hit Stiles like a brick.

The cops she wounded were parallyzed, and a clear, sticky substance was found in the car. Her eyes weren't completely yellow, and her feet had green veins. "Scott," he whispers to his best friend as Deaton further examines the body. "I... I think I know what she is."

Scott's eyes narrow as he says this, thinking about what she could be. Then his eyes open wide. "Kanima?" he replies.

"Kanima," Stiles echoes.

Stiles whips out his phone, and sends a text to Jackson.

To: Jackson Whittemore

We think Tracy's a kanima. Get your ass to the vet.

Just as he hits send and looks up from his phone, Tracy's back splits wide open, and dark red blood splatters them all. Scott stammers backwards, Isaac shields his face with his arms, Malia steps backwards, and Stiles just holds back his nausea. Her spine is laying there, in a pool of blood and muscles, covered in blood. Her spine begins to move, slowly, back and forth. Stiles leans down to look at it, but then something unexpected and particularly disgusting happens. Tracy's spine shoots up out of her back, and whipping Stiles in the face.

Stiles falls face down, and a spiderweb shoots from his hand and onto Tracy, pinning her against the wall as her tail injects Isaac, Malia, Scott, and Deaton with the kanima venom. She yanks her arm off the wall, the spiderweb weak, and hisses at them, her long, sharp teeth bared and half of her face covered in slimy, green scales. She pushes through the mountain ash, not even giving it a second thought, and rushes out the door.

"That's not a werewolf," Malia says.

Then Scott, Stiles, and Isaac all say in unison, "Kanima."

***

"I think I felt my leg move. Oh yeah, that was definitely my leg," Stiles says as the five of them lay on the ground, parallyzed.

"I'd have to disagree," Deaton says. Stiles scowls, then feels his phone buzz in his pocket. "Damn it, that's probably Jackson," he says.

"Can't believe I'm saying this, but we need him," Isaac says.

"That's what Jackson was?" Malia asks.

"Yep," Stiles replies. "Except scalier and more murderous."

Stiles couldn't see her, but he knew that Malia was rolling her eyes. "That's reassuring."

***

Half an hour passes by before Jackson shows up at the vet, followed by Theo. Malia recovered faster than any of them, and raced off to find Tracy at the Sheriff's Station. Stiles groaned and attempted to elbow Theo in the gut as he helped him up. Jackson glared at Theo. He was the only other person in the pack who didn't trust Theo.

"What are you doing here?" Jackson asked. "Last time I checked, this is my pack and I'm the one who experience being a kanima. Speaking of which... where the hell is she?"

"She got away," Scott said as Jackson helped him up, and his legs and arms began to move again. Theo helped up Deaton as Isaac got up, the venom wearing off.

"Let me help," Theo begins. "No," Jackson and Stiles said in unison.

He ignored them. "It doesn't mean that I'm part of the pack, or that you've accepted me or anything like that."

Jackson opens his mouth to say something, but Scott cuts him off. "A little help never hurt anybody." Stiles and Jackson exchanged a look.

Scott walks over to Stiles, helping him walk out the door, as he stumbles over his feet. "Why do you trust him?"

Scott sighs, exasperated. "Because there's no proof that he's a serial killer."

Stiles shakes his head. "I remember Theo from fourth grade," he whispers. "That's not Theo."