Previously on Teen Wolf.

Scott: We agreed to give each other the summer... no calls, no texts. How many are there?

Derek: A pack of 'em. An Alpha pack. They have Boyd and Erica, and I hear there's a leader. He's called Deucalion.

Braeden: Quiet. You hold on tight. You're Allison, right? Where's Scott?

Allison: Lydia, look.

Lydia: I don't know. It doesn't look like much to me.

Allison: It's a pattern. It means something.

Lydia: You really think Scott's gonna know what it is?

Allison: No, but he might know someone who does.

Lydia: How are you so sure that it means anything at all?

Allison: Because that girl wasn't just looking for Scott. It's like she needed to find him. Like she had to. And that means something.

Stiles: What?

Scott: What, what do you mean, "what"?

Stiles: I mean "what," and you know what.

Scott: "What" what?

Stiles: That look you were giving.

Scott: I didn't give a look.

Stiles: Oh, there was a distinct look, Scott.

Scott: What look?

Stiles: The look that says that the last thing you feel like doing right now is going to a party.

Scott: It's not that. It just seems weird going to a different high school's party.

Stiles: What? Would you... [Groans] God, one drink, all right? You'll be fine. I went to nursery school with this girl, okay? She promised to introduce us to all of her friends. So tonight, no Allison, no Lydia. Tonight, we're moving on.

Scott: You're right.

Stiles: That's right I'm right.

Scott: Moving on.

Stiles: Onward and upward.

Scott: Let's do this.

Stiles: That's what I'm talking about. Now look at me.

Scott: Okay.

Scott: How's my breath smell?

Stiles: I'm not smelling your breath.

Scott: Do you have any gum?

Stiles: No. No gum. You're fine.

Scott: Can you at least tell me what kind of party this is?

Heather: It's my birthday!

Danielle: Okay.

Heather: Tonight.

Danielle: Really, tonight?

Heather: Yeah.

Danielle: For real?

Heather: Yeah.

Danielle: You know, your first time is usually sorta gross, and it kinda hurts.

Heather: That's fine with me.

Danielle: No romance? No waiting to fall in love?

Heather: When I fall in love, I want to be good at it.

Danielle: Lord. You at least got yourself a target of opportunity?

Heather: Stiles! Hi.

Stiles: Hey. There's the birthday gir...

Heather: so glad that you made it.

Stiles: Me too.

Heather: Come downstairs with me and help me pick out a bottle of wine.

Stiles: Yes.

[Music playing]

Scott: Hey.

Stiles: Okay. Hey, remember when we were little kids and we used to come down here all the time and then we would... yeah, we never did that.

Heather: Stiles... I just turned 17 today.

Stiles: Mm?

Heather: And you know what I want for my birthday?

Stiles: A bike?

Heather: To not be a 17-year-old virgin. You've never done it before either?

Stiles: Turned 17? No, not yet, no.

Heather: Stiles?

Stiles: Yeah, maybe that other thing too.

Heather: Do you want to? I mean, would you be okay with that?

Stiles: Yeah. Would I be okay with that? I believe so, yeah, um...Okay. No, yeah, very... Okay. Um, wait, wait, wait. Wait. I don't have any, uh...

Heather: My brother has some in the upstairs bathroom.

Stiles: Yeah?

Heather: Yeah.

Stiles: Okay, sho...

Heather: You should go get them. Go.

Stiles: Going.

Heather: Go.

Scott: This isn't the talk we were gonna have, is it?

Allison: I need to show you something.

Stiles: Yes, yes, yes!

Heather: Stiles? Okay, this isn't funny. Ahhh...

Stiles: Okay. Only got one. I figured, you know, if we needed more, I could... Heather?

Isaac: You know, I'm starting not to like this idea. Sounds kinda dangerous. You know what? I definitely don't like this idea, and I definitely don't like him.

Derek: You'll be fine.

Isaac: Does it have to be him?

Derek: He knows how to do it. I don't. Be more dangerous if I tried doing it myself.

Isaac: You know Scott doesn't trust him, right? You know, personally, I'd... well, I'd trust Scott.

Derek: Do you trust me?

Isaac: Yeah. I still don't like him.

Derek: Nobody likes him.

Peter: Boys. F.Y.I., yes, coming back from the dead has left my abilities somewhat impaired, but the hearing still works. So I hope you're comfortable saying whatever it is that you're feeling straight to my face.

Derek: We don't like you. Now shut up and help us.

Peter: Fair enough. Relax. I'll get more out of you if you're calm.

Isaac: How do you know how to do this, again?

Peter: It's an ancient ritual used mostly by alphas, since it's a skill that requires quite a bit of practice. One slip, and you could paralyze someone. Or kill them.

Isaac: You... You've had a lot of practice, though, right?

Peter: Well, I've never paralyzed anyone.

Isaac: Wait, does that mean that you...

Peter: Wait, I see them.

Derek: What'd you see?

Peter: [Panting] It was confusing. Um, im... images. Vague shapes.

Derek: But you saw something.

Peter: Isaac found them.

Derek: Erica and Boyd?

Peter: I barely saw them. I mean, glimpses.

Derek: But you did see them.

Peter: And worse.

Derek: Deucalion.

Peter: He was talking to them. Something about time running out.

Isaac: What does it mean?

Derek: He's gonna kill them.

Peter: No, no, no, no, no, he didn't say that. He did make them a promise that by the full moon that they'd both be dead.

Derek: The next full moon?

Peter: Tomorrow night.

Derek: I don't see anything.

Scott: Look again.

Derek: How is a bruise gonna tell me where Boyd and Erica are?

Scott: It's the same on both sides. Exactly the same.

Derek: It's nothing.

Lydia: Pareidolia. Seeing patterns that aren't there. It's a subset of apophenia.

Scott: They're trying to help.

Derek: These two. This one, who used me to resurrect my psychotic Uncle. Thank you. And this one, who shot about 30 arrows into me and my pack.

Stiles: Okay, all right, now, come on. No one died, all right? Look, there may have been a little maiming, okay, a little mangling, but no death. That's what I call an important distinction.

Allison: My mother died.

Derek: Your family's little honor code killed your mother. Not me.

Allison: That girl was looking for Scott. I'm here to help him, not you.

Derek: You wanna help? Find something real.

Scott: Derek... Give her a chance. Okay, they're on our side now.

Derek: Well then maybe you should tell her what her mother was actually trying to do that night.

Stiles: Okay, what would a pack of alphas want with Erica and Boyd?

Scott: I'm not sure it's them they want.

Stiles: Okay, what, like Derek? Like they're recruiting? Hey, Scott. You coming?

Coach: The stock market is based on two principles. What are they? Yes, McCall, you can go to the bathroom. Anybody else?

Scott: Uh, no, coach, I know the answer.

Coach: Hahahahaha Oh, you're serious.

Scott: Yes. Risk and reward.

Coach: Wow! Who are you? And what have you done to McCall? Don't answer that. I like you better. I like you better. Does anybody have a quarter? A quarter.

Stiles: Yep.

Coach: Stilinski, I think you, uh... You dropped this. And congratulations. Risk and reward. Put the quarter in the mug, win the reward. Okay, watch coach. That's how you do it. Okay. Danny. Risk, reward.

Danny: What's the reward?

Coach: You don't have to take the pop quiz tomorrow.

Danny: Coach, it's not a pop quiz if you tell us about it.

Coach: Danny, you know, I really expect more from you at this point. Really. McCall. Risk, reward. The risk: If you don't put that quarter in the mug, you have to take the pop... the... the quiz. And... and you have to write an essay. Risk, more work. Reward... No work at all. Or choose not to play.

Scott: But isn't this just chance?

Coach: No. You know your abilities, your coordination, your focus, past experience... all factors affecting the outcome.So what's it gonna be, McCall?More work, no work, or choose not to play?

Scott: No play.

Coach: Okay. Who's next? Who wants the quarter? There ya go! There's a gamblin' man! Come on! Step up, step up. [Claps] All right, Stilinski.

Sheriff: Stiles.

Stiles: Yeah, coach, I got it.

Sheriff: Stiles.

Stiles: I couldn't find her. I just figured she'd hooked up with her other friends. Has no one really seen her since last night?

Sheriff: No. We put out an A.P.B., but, Stiles, all her friends say you were the last person who saw her.

Stiles: Me?

Sheriff: We hope that it's just a series of bad decisions based on too much to drink. But if you remember anything else, you call me. All right?

Stiles: Yes!

Coach: Reward! Okay, who's next? Greenberg, put your hand down. You don't have a chance.

Lydia: I want one.

Allison: Which one?

Lydia: The straight one, obviously.

Allison: What if it's not a symbol?cWhat if it's actually a logo?

Scott: So you think they kidnapped Heather to turn her?

Stiles: Derek says it's easier to turn teenagers.

Scott: But what would a pack of alphas need with a beta?

Stiles: Scott, I don't know. I don't care. All right? This girl... Our moms were best friends before mine died, all right? We used to take frickin' bubble baths together when we were three. I gotta find her.

Scott: Then we need Isaac to remember.

Stiles: How? Peter and Derek couldn't do it. You know any other werewolves with a better trick?

Scott: Maybe not a werewolf. But someone who knows a lot about 'em.

Deaton: Obviously, it's not going to be particularly... Comfortable. But if we can slow your heart rate down enough, you'll slip into a trance-like state.

Isaac: Like being hypnotized.

Deaton: Exactly. You'll be half transformed. It'll let us access your subconscious mind.

Scott: How slow does his heart rate need to be?

Deaton: Very slow.

Derek: Okay, well, how slow is very slow?

Deaton: Nearly dead.

Isaac: It's safe, though, right?

Deaton: Do you want me to answer honestly?

Isaac: No. No, not really.

Stiles: What?

Derek: Look, if it feels too risky, you don't have to do this.

Deaton: Get him back under. Hold him.

Derek: We're trying!

Deaton: Now, remember, only I talk to him. Too many voices will confuse him and draw him out. Isaac? Can you hear me?

Isaac: Yes. I can hear you.

Deaton: This is Dr. Deaton. I'd like to ask you a few questions. Is that all right?

Isaac: Yes.

Deaton: I want to ask you about the night you found Erica and Boyd. I want you to remember it for me in as vivid detail as possible, like you're actually there again.

Isaac: I, I don't wanna do that. I don't... I don't wanna do that. I don't wanna do that.

Deaton: Isaac, it's all right. Just relax. They're just memories. You can't be hurt by a memory.

Isaac: I don't wanna do that.

Deaton: It's all right.

Isaac: I don't wanna do that.

Deaton: Relax. Relax. Good. Now let's go back to that night. To the place you found Erica and Boyd. Can you tell me what you see? Is there some kind of building? A house?

Isaac: It's not... it's not a house. It's stone. I think marble.

Deaton: That's perfect. Can you give me any other descriptors?

Isaac: It's dusty, so empty. Like an abandoned building?

Deaton: Isaac? Isaac?

Isaac: Someone's here. Someone's here.

Deaton: Isaac, relax.

Isaac: No, no, no, they see me, they see me!

Deaton: Just memories. You won't be hurt by your memories. Just relax. Relax. Good. Now tell us what you see. Tell us everything.

Boyd: But I can't control it. Neither of us will.

Isaac: I hear him. He's talking about the full moon, about being out of control when the moon rises.

Deaton: Is he talking to Erica?

Isaac: I think so, I can't... I can't see her, I ca... I can't... I can't see either of them.

Deaton: Can you hear anything else?They're worried.They're worried what they'll do during the moon.They're...Worried that they're gonna hurt each other.

Derek: If they're locked in together on the full moon, they're gonna tear each other apart.

Deaton: Isaac, we need to find them right now. Can you see them?

Isaac: No.

Deaton: Do you know what kind of room it is? Is there any kind of a marker? A number on a door? A sign?

Isaac: They're here. They... They...

Deaton: It's all right.

Isaac: No.

Deaton: Just tell us...

Isaac: They see me. They found me. They're here!

Derek: This isn't working. Isaac, where are you?

Isaac: I can't see them. It's too dark!

Derek: Just tell me where you are.

Deaton: You are confusing him.

Isaac: I can't see!

Derek: Isaac, where are you? Just tell me where you are.

Deaton: His heart rate... he could go into shock.

Scott: Derek, let him go!

Derek: Isaac, where are you? What did you see?

Isaac: A vault! It's a bank vault! I saw it! I saw the name. It's, uh... B-beacon hills first national bank. It's, um... it's an abandoned bank, and they're keeping them locked inside, inside the vault. What?

Stiles: You don't remember what you said right before you came out of it, do you?

Isaac: No.

Stiles: You said when they captured you that they dragged you into a room and that there was a body in it.

Isaac: What body?

Stiles: Erica. You said it was Erica.

Derek: She's not dead.

Stiles: Derek, he said, "there's a dead body. It's Erica." Doesn't exactly leave us much room for interpretation.

Derek: Then who was in the vault with Boyd?

Stiles: Someone else, obviously.

Scott: And maybe it was the girl on the motorcycle. Okay, the one who saved you?

Isaac: No, she wasn't like us. And whoever was in the vault with Boyd was.

Derek: What if that's how Erica died?

Stiles: They, like, pit them against each other during the full moons and see which one survives. It's like werewolf thunderdome.

Derek: Then we get them out tonight.

Deaton: Be smart about this, Derek. You can't just go storming in.

Derek: If Isaac got in, then so can we.

Deaton: But he didn't get through a vault door, did he?

Scott: We need a plan.

Derek: How are we gonna come up with a plan to break into a bank vault in less than 24 hours?

Stiles: Uh, I think someone already did. "Beacon hills first national closes its doors three months after vault robbery." Doesn't say here how it was robbed, but it probably won't take long to find out.

Derek: How long?

Stiles: It's the Internet, Derek. Okay? Minutes.

Sheriff: Boys. Hey, time to wake up. Boys. Boys! I got to get to work. You two get to school.

Stiles: Dad! Heather?

Sheriff: No, nothing yet.

Stiles: Ten hours and nothing.

Scott: We're gonna find something.

Stiles: Finding something doesn't make Erica any less dead or Boyd any less about-to-be-dead.

Scott: Well, we still have time.

Stiles: Is this whole, like, "remain optimistic "in the face of complete and utter disaster" thing a part of the "be a better Scott McCall" program?

Scott: Uh, not if it doesn't work.

Stiles: No, it works. Oh, dad! Dad? Dad!

Lydia: So mystery girl leaves a bruise on our arms that turns out to be the logo for a bank? [Scoffs] What's she trying to do? Give us investment advice?

Allison: Not at this bank. It's been closed for years.

Lydia: Why aren't you telling Scott?

Allison: Because according to someone, I need to find something real. Which reminds me, um, I can't drive you home today. I have an errand to run after school.

Scott: All right, so we meet at Derek's at 5:00 to go over the plan, and then we don't get started until dark.

Stiles: 'Kay. What do we do till then?

Scott: What, right now? We've got English.

Sheriff: Okay. You see this? This is how they got in. It's a rooftop air conditioning vent. Leads down inside into the wall of the vault, which is here. Okay? One of the robbers was lowered into this shaft Now, that space is so small, it took him about 12 hours to drill into that wall, which is stone, by the way. Then throughout the rest of the night, they siphoned the cash up to the guys back on the roof through that one little shaft in the wall.Boom.

Scott: Can we fit in there?

Stiles: Yes, we can, but very, very barely. And they also patched the wall, obviously, so we're gonna need a drill of some kind. I'm thinking maybe a diamond bit...

Derek: look, forget the drill.

Stiles: Sorry?

Derek: If I go in first, how much space do I have? What do you... what do you think you're gonna do, Derek? You gonna punch through the wall?

Derek: Yes, Stiles, I'm gonna punch through the wall.

Stiles: Okay, okay, big guy. Let's see it. Let's see that fist. Big, old fist. Make it, come on. Get it out there. Don't be scared. Big, bad wolf.Yeah, look at that.Okay, see this?That's maybe 3 inches of room to gather enough force to punch through solid co...

Stiles: He could do it.

Derek: I'll get through the wall. Who's following me down?

Peter: Don't look at me.I'm not up to fighting speed yet, and honestly, with Isaac out of commission, you're not looking at very good odds for yourself.

Derek: So I'm supposed to just let them die?

Peter: One of them is already dead.

Derek: We don't know that.

Peter: Do I have to remind you what we're up against here? A pack of alphas. All of them, killers. And if that's not enough to scare your testicles back into your stomach, try to remember that two of them combine bodies to form one giant Alpha. I'm sure Erica and Boyd were sweet kids. They're gonna be missed.

Stiles: Could someone kill him again, please?

Peter: Derek, seriously? Not worth the risk.

Derek: What about you?

Stiles: Yeah, if you want me to come...

Derek: Not you.

Stiles: Got it.

Scott: I don't know about Erica. But if Boyd's still alive, we have to do something. We have to try.

Derek: But?

Scott: Who's the other girl? The one locked in there with Boyd?

Allison: Ms. Morrell?

Ms. Morrell: Keep your mouth shut, and listen close. You have no idea what you just stepped into. Right now you've got maybe 20 seconds to get your ass hidden.

Allison: What are you doing?

Ms. Morrell: Get in that storage closet over there.Lock the door.When you hear the fighting start, that's when you come out.

Allison: What fighting?

Ms. Morrell: You'll hear it. Now, go!

Stiles: I can't take waiting around like this, you know? It's nerve-racking. My nerves are racked. They're severely racked. Racked.

Peter: I could beat you unconscious and wake you when it's over.

Stiles: You think Erica's really dead?

Peter: You think I really care?

Stiles: I just... I don't understand the bank, though, okay? Wha... like, why wouldn't they chain them up in some underground lair or something? They're an Alpha pack, right? So shouldn't they have a lair?

Peter: They're werewolves, not bond villains.

Stiles: Wait a sec. Wait a sec. Maybe they're living there. You know? Like, maybe the bank vault reminds them of their little wolf dens.

Peter: Wolf dens?

Stiles: Yeah, wolf dens.Where do you live?

Peter: In an underground network of caves hidden deep in the woods.

Stiles: Whoa, really?

Peter: No, you idiot. I have an apartment downtown.

Stiles: Okay, fine, but still, that just proves that there's something up with the bank. And why wait around for the full moon, huh? Why not just kill them whenever they want to?

Peter: Maybe they think it's poetic.

Stiles: They've already had three full moons to be poetic.

Peter: And here you've only had one full hour to be so annoying...

Stiles: No, go ahead, finish what you were saying. I'm an... I'm annoying. What were you gonna say there?

Peter: What are the walls made of?

Stiles: What? Uh... I don't know, like, wood and brick or...

Peter: No, the vault, the vault, the walls, what are they made out of? Where would it say that? Doesn't say anything. Where... where would it say the materials, the type of stone?

Stiles: Oh.. Oh, hang on. Yeah, here, hang on. Here. It's gotta be in there.

Derek: What?

Scott: There's just something I can't get out of my head.

Derek: The moon's rising, Scott. What is it?

Scott: Risk and reward.

Derek: Which means what?

Scott: We're not measuring the risk with enough information. We don't know enough.

Derek: We know time's running out.

Scott: Yeah, but think about it. They put the triskele on your door four months ago. What have they been doing all this time? Why wait until now?

Derek: We don't have the time to figure out every little detail. Okay, but what if this detail, the reason why they waited... what if it's the most important one?

Derek: Then we do nothing. And Boyd and Erica are dead. I know what I'm risking. My life for theirs. And I won't blame you if you don't follow me.

Stiles: There, that's it.

Peter: Hecatolite.

Stiles: Is that awful? That sounds awful.

Peter: Get 'em on the phone. Call them. Now!

Stiles: Okay, why?

Peter: 'Cause Boyd and that girl aren't gonna kill each other. They're gonna kill Derek and Scott.

Derek: Boyd? Boyd? It's me. It's Derek.

Scott: Stiles, now is not the best time.

Stiles: Scott! Scott! No, listen to me, okay? Look, you gotta get outta there. Look, the walls of the vault are made with a mineral called hecatolite. It scatters the moonlight.

Scott: What does that mean?

Derek: We're here to get you out, okay?

Stiles: Look, it keeps the moonlight out, okay? They haven't felt the full moon in months.

Peter: Okay, think of it like the gladiators in the Roman colosseum. They used to starve the lions for three days, making them more vicious, more out of control. Deucalion has kept them from shifting for three full moons, diminishing their tolerance to it.

Stiles: Scott, they're gonna be stronger...

Peter: More savage, more bloodthirsty, Scott, they're the lions. They're the starved lions, and you and Derek just stepped into the colosseum.

Scott: Derek, we got a problem, a really big problem.

Derek: Cora?

Scott: Who?

Derek: Cora?

Cora: Derek, get out. Get out now!

Stiles: Scott? Hey, Scott! Scott!

Scott: No. No! Wait!

Stiles: Scott? Scott, are you hearing this? Scott!

Deucalion: Don't kid yourself, Marin. It's not the first time you've gotten your hands dirty.

Scott: You know her?

Derek: She's my sister, my younger sister.

Scott: What the hell is she doing here?

Derek: Like I have a clue. I thought she was dead!

Allison: Look out!

Derek: No! Don't break the seal!

Allison: Boyd!

Scott: Don't touch her!

Derek: What were you thinking?

Allison: That I had to do something.

Scott: She saved our lives.

Derek: Yeah, and what do you think they're gonna do out there? Do you have any idea what we just set free?

Allison: You want to blame me? Well, I am not the one turning teenagers into killers.

Derek: No. No, that's just the rest of your family.

Allison: I made mistakes. Gerard is not my fault.

Derek: And what about your mother?

Allison: What do you mean?

Derek: Tell her, Scott.

Allison: What does he mean, Scott? What does he mean?