Scott, Stiles, and Allison wake up in ice baths in a pure white room. They climb out of the tubs and look around. Behind them, they see the nemeton growing out of the floor. They approach slowly.
Scott gets closest and checks the tattoo on his arm when he sees the growth rings of the nemeton. He recalls the conversation he had with Derek when he asked him to help make his tattoo permanent and realizes that he's been connected to the nemeton somehow and this was why he was tracing the circles.
Scott touches the nemeton and instantly finds himself in Beacon Hills Preserve. He sees himself using his phone as a flashlight and looking through the fallen leaves for his inhaler. He watches himself find Laura's body and then tumble down the hill. Then he sees himself attacked by the alpha. Scott reacts in shock and steps back, bumping into the nemeton.
Stiles also finds himself in the Preserve, reliving the actions of the first episode of the series. He and Scott are looking for the body. Stiles watches himself get caught by his father and the deputies. His father says that he's going to walk him back to his car. Stiles backs up, and like Scott, he bumps into the nemeton.
Allison finds herself in the car with her mother. Victoria is telling her that Chris is a highly respected private security consultant and a federally licensed firearms dealer. She's explaining to Allison that Chris keeps weird hours because he has a weird job. Allison complains that he takes off in the middle of the night, rushing around with duffel bags full of weapons.
Suddenly, Allison gasps. Scott is in the road. Victoria swerves their SUV to avoid hitting him. Allison accuses her mother of almost killing him. Victoria counters that he ran into the middle of the road. Allison tells her that they have to go back. Victoria doesn't want to, but she eventually does at Allison's insistence.
Allison gets out of the car and follows footprints Scott left into the woods. She finds Scott's inhaler on the ground. Victoria rushes to her side and orders her to get back in the car. They both hear a wolf howl, and Victoria tosses the inhaler. It lands at current Allison's feet. She finds herself standing next to the nemeton.
"I saw it. I saw where it is!" Scott tells them. Stiles adds that they passed it the night they were looking for the body and the tree is big. Cut down, but very big. Allison says that she was there too and they almost hit someone with their car. Scott realizes that she almost hit him.
The three of them stop talking when they see that Deaton, Lydia, and Isaac are staring at them. "You guys were out a long time," Isaac says. "How long is a long time?" "16 hours," Deaton tells him. The full moon rises in less than four hours.
Cora gives Derek a drink of water as she pets the back of his neck. He's weak and looks at her in surprise. "You're okay." She tells him that she's doing a lot better than he is right now because of him. Peter gripes that he hopes it wasn't for nothing. The moon is rising and he drained himself all the way to the red, while there's a fully charged alpha on her way to rip him apart.
Derek replies that he'll be fine in a few hours. "I sincerely hope so, because a few hours is all that you have."
At the Animal Clinic, Stiles argues with Scott about him going back to the alpha pack. Scott tells him that he made a deal with Deucalion. "Does anyone else think that sounds a lot like a deal with the devil?" Stiles says. Isaac asks why Scott wants to go back with them, and Scott says that he doesn't think they can beat Jennifer without them. Allison appeals to Deaton to change Scott's mind, but Deaton agrees with his plan. "So we're gonna trust him? The guy that calls himself Death, the Destroyer of Worlds, we're gonna trust that guy?" Isaac asks.
Deaton says they should use Deucalion to their advantage and use him as bait.
The Animal Clinic door opens, and everyone looks concerned. Deaton goes out and finds Ethan in the lobby. "I'm looking for Lydia." He says that he needs her help. Stiles comes into the doorway. "With what?" "Stopping my brother and Kali from killing Derek."
In the root cellar, Chris checks the sonic emitter. Melissa asks him if it's still working. "Yeah, but not for much longer." She then asks if anyone else is feeling an unbearable itch that they can't scratch. "Well, not before you said something, but now, yes, I do," the Sheriff answers. Melissa asks if Jennifer is really going to come down there and slash their throats. The Sheriff replies that no, she'll come down and strangle them with a garrote and then slash their throats.
The wind starts to pick up, and the root cellar shudders. Dust blows down on them.
At Derek's loft, Ethan tells Derek that they know about the lunar eclipse and that Kali isn't going to wait around for it to level the playing field. She's coming and bringing Aiden with her. Peter is convinced that they should go. "You want me to run?" Derek asks Peter. "No. I want you to stay and get slaughtered by an alpha with a psychotic foot fetish. OF course I want you to run."
Cora adds that if Derek wants to fight and die for something, he should do it for something meaningful. Derek asks them how they know he's going to lose. "We don't. But I bet she has an idea," Peter replies, and gives a meaningful look at Lydia. Peter asks her what she feels. "I feel like I'm standing in a graveyard."
Scott, Allison, and Isaac go to the Argents' apartment. Scott is on the phone with Stiles and tells him to grab anything. "Stiles, I'm not smelling your dad's boxers. Socks? Okay, I'll smell the socks." Isaac asks what he should do, and Allison tells him to find something of her dad's with a strong scent.
Allison heads into Chris's office and stops short when she finds Rafael McCall and two deputies with him. "Quite an arsenal your father's got here, young lady," McCall says. Scott steps into the doorway and asks his dad what he's doing there. Agent McCall replies that he's following the only lead he has. He asks Scott to take a seat so they can talk. Agent McCall also calls out to Isaac to come in and sit down.
"How do you know my name?" Isaac asks. "Your name's one of the few things I know," McCall answers. He tells them that he's stumbling around in the dark looking for clues and is tired of it. Scott replies that he learned a long time ago that his dad didn't have a clue. McCall doesn't want to drag his own son into an interrogation room.
The alarm in Derek's loft goes off, and Kali knocks it off the wall. "Where is he?" she demands. Lydia snaps her fingers and glances at Ethan. "I think he said he was heading out to do some shopping, run a few errands, the usual werewolf afternoon." Kali is not impressed and threatens Lydia. Lydia tells her that she needs a pedicure and offers to give her a referral.
Aiden growls as Kali closes in on Lydia, and Kali turns to face him. "Oh, really?"
Meanwhile, Derek and Cora get into Derek's truck. Peter tells them not to call until they're at least 100 miles away. Derek doesn't look pleased, but he drives off.
Agent McCall tells the kids that he's more than a little disturbed at the number of missing parents and especially by the fact that it's Stiles's father, Allison's father, and Scott's mother. Isaac raises his hand. "Mine are both dead." Agent McCall is not having any of his attitude. He knows that they know something and is willing to keep them there all night if he has to.
Scott rolls his eyes, but he sees Allison's flash bomb arrowheads.
Kali circles around Aiden and asks him if he took his assignment too seriously. Aiden tells her that Lydia is not the problem. "Maybe the problem is where your loyalties lie." Lydia asks Ethan if this is about to get really violent. "Probably."
Then Jennifer drops in from the roof, breaking through the glass ceiling. She glares at Kali. "So, who wants to go first?" Ethan holds Lydia protectively while Kali and Jennifer fight.
Jennifer easily dodges Kali's kicks and punches, then lands a hit on her that sends her flying. Aiden does even less well. Ethan then tears his shirt off and goes to join his brother. They try to meld, but Jennifer grabs them by their throats and forces them apart.
Kali gets up to face off against Jennifer again, and Jennifer tells her to look at her face. "Do you know what it takes to be able to look like this, to be able to look normal?" "I don't care." "It takes power." Jennifer then lifts all the broken glass and debris off the floor with magic. Kali screams that she should have ripped her head off, and then Jennifer hurls the glass at Kali. She is impaled all over and falls dead.
Ethan and Aiden meld together to form Voltron, and Jennifer turns to face them. They take a single swing, and she ducks and spins around, then grabs them by the neck and breaks it over her shoulder. Lydia is terrified.
Stiles races toward the Preserve and peers out the windshield at the growing storm.
At the Argents' apartment, Scott tells his father that he can't keep them there. Agent McCall replies that he has a table in front of him full of probably cause. Allison recalls the explanation her mother gave her. Chris is a highly respected private security consultant and a federally licensed firearms dealer. "That means he has to own a few weapons." She points out the 175-lb draw tactical crossbow, a steel marine combat knife, a .50AE Desert Eagle. "Smoke grenade with pull-ring igniter." Allison picks up the smoke grenade and pulls the ring.
She tosses the grenade at Agent McCall, and they all run.
The storm outside gets worse, and Stiles loses control of his car. He slams into a tree and is knocked out.
Jennifer goes after Lydia. Lydia asks her what she wants. "I want you to do what you do best, Lydia. I want you to scream." Lydia screams, and on the way out of town, Derek pulls over the car. "What the hell was that?" Cora asks him. He gives her a panicked look. "Lydia. We have to go back."
Scott, Isaac, and Allison arrive at Beacon Hills Preserve. Scott tells Allison that her idea was awesome. Isaac points out that he still hasn't heard anything from Stiles. Scott is worried, but they don't go look for him.
Allison, Isaac, and Scott meet up with Deucalion at the overlook point. "Cutting it a little close, aren't we, Scott?" Duke asks. Scott wants to know where the other alphas are, and Duke tells him they're occupied. He thinks he and Scott will be enough, though.
Scott tells Isaac and Allison to find Stiles and get to the root cellar. He and Duke will keep Jennifer busy long enough for them to save the parents.
Derek and Cora head back to the loft. Cora comforts Lydia while Derek faces Jennifer. "You did this for me?" "For us. For anyone who's ever been their victim." Derek yells at her to stop talking like a politician. She then asks him to think about someone else's cause, that he could save Scott's mother and Stiles' father. Jennifer needs a guardian. If Derek chooses to go with her, he can fill that role instead of the three parents she took.
Derek tells her that he can't help her. He's not even an alpha anymore. She says that she just needs him to help her get Deucalion in the right place at the right time. "You just killed three of them on your own. What do you need me for?" She says that Deucalion at his strongest plus Scott is more than she can take on her own. Cora warns Derek not to trust her.
Jennifer explains that there's only going to be a 15 minute window when the lunar eclipse will be in play. "There's no decision to struggle with. Help me kill him and the others live."
Allison and Isaac walk through the woods looking for the nemeton. The wind is high. Isaac can't pick up a scent, but he can hear the sonic emitter. They find the nemeton and the root cellar and head down. As they enter, the root cellar starts to collapse.
Allison goes to her father and kisses him on the head. The Sheriff asks where Stiles is and Melissa asks about Scott. Isaac assures them they're both on their way. The root cellar collapses further.
Back at the loft, Cora and Lydia get up to leave. Cora says they need to find help, even though they don't know from who. As they're leaving, they hear a sound behind them and the twins separate. Cora realizes that they're alive.
Scott and Duke head to the abandoned distillery. Scott tells Duke that the first day of class Jennifer sent them all a text message, which was the last line from Heart of Darkness. "I got a message of my own to send her."
Jennifer watches a countdown on her phone for the lunar eclipse and gets a video message from Scott. He shows her the revenge spiral that Ennis clawed into the wall of the distillery. "You talk about balance, about saving people. We know what you really want and now you know where to find us."
The Sheriff, Melissa, and Chris pull off their ropes, but the ceiling of the cellar falls in. They try to head for the stairs, but the stairway collapses too.
Cora and Lydia bring the twins to the Animal Clinic. They put each one on a table, and Lydia takes Aiden's hand. Cora asks Deaton if he can save them, but he has they have to start healing on their own.
Scott and Deucalion wait in the distillery for Jennifer and Derek. Scott clearly wasn't expecting Derek to be there with her. "What are you doing?" "This might be hard to believe, but I'm actually trying to help you." Deucalion finds the brother against brother theme very American.
He puts away his cane and asks Jennifer if she gathered her herbs and prayed to her ancient gods and her oak trees. "Should we show them why you needed to sacrifice nine innocent people just to face me?" As he speaks, Deucalion starts to shift. His skin goes black, and he eyes glow red.
Chris checks the stairway and declares it blocked. The beams holding up the ceiling start to break. Isaac holds it up long enough for the Sheriff and Melissa to get out of the way.
Derek attacks Deucalion, but Duke just grabs his arms and holds them down. Jennifer takes her shot, attempting to hit him with the same force punches that she used on the others, but the power just skirts around him. Duke them grabs them both by their throats and lifts them up. He tosses them, and Derek tries to attack again. Duke hits him with one blow, sending him across the distillery and into a stack of tires.
Duke backhands Jennifer and then grabs her by her hair. He brings her over to Scott and orders him to kill her. When Scott hesitates, Deucalion alpha roars at him, bringing Scott to his knees and forcing him to shift. Duke tells him that the parents are dying because the the storm Jennifer has conjured is burying them alive. "Kill her, and it ends."
Jennifer warns Scott that if he kills her, it won't end there. Duke will make him kill everyone he loves. Duke tries to sway him. "Become the alpha you're meant to be. Become a killer." Scott tells him that the parents aren't dead yet. Duke smirks. "Who's going to save them? Your friends?" Scott stands and his eyes flash yellow. "My pack."
Isaac struggles to hold up the ceiling beam.
Deaton gives Ethan and Aiden oxygen and some shots.
Duke rushes over to Scott and grabs him by the back of the neck. He forces him to walk to Jennifer. "Maybe you just need a little guidance." Scott tells Deucalion that he forgot to tell him something. "Something that Gerard told me. 'Deucalion isn't always blind.'"
Scott slips the flash bombs out of his pocket and throws them all on the ground. All three wolves stagger around.
The lunar eclipse then hits, and the three of them shift back to human. Scott gets up to find Jennifer missing.
Isaac can't hold the ceiling beam anymore. Everyone else joins in trying to help, and then Stiles jumps down into the cellar with a metal bat. The Sheriff looks at him. "I always said aluminum was better than wood." They hug.
Jennifer returns to the distillery in Darach form. Derek hides behind a stack of crates. Jennifer attacks Scott, tossing him back, then goes after Deucalion. She bashes his head into the floor repeatedly.
Derek jumps up from his hiding place and calls her name. "He doesn't know." "Know what?" "What you really look like. He knows the cost of bringing Kali into his pack, but he's never seen the price you paid." She agrees that he hasn't, so she heals Deucalion's eyes.
When Deucalion turns to her, he still sees her glamor. She goes to strike him but falters and collapses. "What is this?" she asks Derek as he catches her. He explains that healing Duke made her weak. She won't have her strength back for a few minutes. "Then you do it. Kill him."
"No. Like my mother used to say, I'm a predator. I don't have to be a killer." Then he grips her throat and orders her to let the parents go. She shoves him back and hits him a few times in the face, looking betrayed. She leaves him and turns back to Deucalion, but he gets up and goes after her again.
Jennifer slams him against one of the distillery barrels. She keeps hitting him, and he endures the punishment, waiting for the lunar eclipse to end. As soon as it does, his eyes flash blue. "Your 15 minutes are up." Derek tosses her into the middle of the room.
Scott goes to attack her, but Jennifer tosses up a mountain ash circle. Scott skids to a stop just outside it. Jennifer tells them that now that she doesn't have Derek, she's just going to take the parents. In a few minutes she'll have enough power to kill a demon wolf.
Scott glares at her and puts his hands against the barrier. He starts pressing, and his eyes glow yellow. He keeps pressing, and his eyes turn red. Scott takes one step across the barrier, then another. When the barrier collapses, Jennifer falls. "How did you do that?" "I'm an alpha now," Scott tells her. Deucalion gets up from the floor as Scott tells Jennifer to stop the storm.
Scott declares that if she doesn't stop the storm, he'll kill her and he doesn't care about the color of his eyes. "It won't change the color of mine, so allow me," Duke says. He rushes forward and slashes her throat.
The storm stops, and everyone in the cellar celebrates.
Cora helps Ethan to his feet, and Aiden tells Lydia that he knew that she cared about him.
Scott calls Stiles to check if everyone is okay. Stiles asks him if he's okay, and Scott turns to look at Derek, who just shrugs. "Sort of," Scott replies. Stiles asks him to bring a ladder when he comes to rescue them all, and the Sheriff laughs.
Derek and Scott face Deucalion. "My mother told me you were a man of vision once," Derek says to Duke. "We're letting you go because we hope you can be that man again." Scott adds, "But if you're not, then having your eyesight back won't matter, because you'll never see us coming."
Derek and Scott leave Duke at the distillery.
In the Argents' apartment, Allison asks her father if the guns are going back to storage. "That's the plan." "What if I've got a different plan." She says that activating the nemeton turned Beacon Hills into a beacon again and would draw things there. Allison says they will have a new code: We protect those who cannot protect themselves.
Derek and Cora leave the loft, with Scott voice-overing that he doesn't know if Derek is coming back but part of him hopes so and that maybe he'll be okay somewhere else.
Agent McCall, however, is sticking around. He knocks on Scott's door, and Scott closes it in his face.
Scott walks into school, explaining that he and Stiles both feel the darkness around their hearts every day. When Scott feels it, it's like looking into the heart of an immense darkness. Deaton asks him what he does instead. "I look for my friends."
Aiden and Lydia chat near her locker. Danny and Ethan come out of a classroom holding hands. Allison and Isaac talk and laugh as they come down the stairs. Stiles claps Scott on the shoulder, and they head down the hallway.
Deaton asks Scott about Jennifer. "When we went back inside the distillery, her body was gone."
Jennifer claws her way through the dirt toward the nemeton, begging it to give her power. As she reaches it, a clawed hand grabs her wrist. Peter turns her around, and she laughs. "Of course it's you. Everyone else suffers, but you come out on top. And now that Scott's an alpha, you'll be able to steal it from him." Peter smirks. He slashes her throat. "I. Am. The alpha. I've always been the alpha!!!"