Stiles goes with Scott to get a tattoo, though he's afraid of needles and doesn't like the design Scott got. As they leave, they run into Allison and Lydia, and it gets awkward because Scott and Allison have broken up. A deer runs into Lydia's car, starting a string of weird animal behavior. Stiles starts looking into deer accidents and tries to avoid going to school, but his dad makes him. Scott wants to ask Derek about fixing his tattoo, but Stiles points out that Derek is probably more concerned with finding Boyd and Erica. In class, he notes that Lydia was bitten by her dog. They are then attacked by birds in the classroom. Once Stiles gets out of class, he meets Scott and Derek at the Hale House where he helps hold Scott down while Derek burns his tattoo into place. Afterward, Stiles intimates that he's been helping Derek look for Boyd and Erica without Scott's knowledge.
Stiles and Scott are going to a birthday party for one of Stiles's old friends. She's turning 17 and for her birthday wants to have sex. She kisses Stiles as soon as he arrives and brings him into the basement. They start to make out, but don't have a condom, so Stiles goes upstairs to the bathroom to find out. He finds an XXL, which is too big, but goes back down to continue with Heather anyway, only she's gone missing. Lydia and Allison find Scott and tell him about the symbol on their arms, so he arranges a meeting with Derek the next day. Stiles doesn't take sides. Later, the Sheriff shows up to report that Heather is missing and Stiles was the last person to see her.
Isaac can't remember where he saw Boyd and Erica, so they put him in an ice bath under Deaton's direction. Stiles helps hold him down. When Isaac comes out of it, Stiles tells him that he said Erica was dead. They know they're being held in the Beacon Hills First National bank vault, and Stiles is confident that he can find details about the robbery pretty quickly. He's wrong and ends up having to ask his dad, who worked the case. He gets plans of the building and a recap of how the robbers broke in. With this, he and Scott go to Derek's loft, and Stiles sketches out their plan to break in. He doesn't think Derek can punch through the stone wall, and Derek amuses himself by punching Stiles's hand to prove him wrong. While Derek and Scott go to break in, Stiles and Peter wait. Stiles still thinks it's meaningful that they kept them for 3 months, and they realize that the material of the vault has kept Boyd and the other Werewolf from feeling the effects of the full moon, making them more rabid.
Lydia calls Stiles when she ends up at a pool and finds a dead body. He realizes that the person has been killed by the same methods as the others and that the boy had a purity ring. He reports the murder to Scott, who believes Boyd and Cora are responsible. Stiles follows Lydia home and they talk about what's going on with her. Stiles then goes to the hospital where Melissa shows him the other bodies, which makes it obvious that it wasn't Boyd and Cora. She shows him Heather, not knowing that he knew her, and then tells him about Caitlin and Emily. He finds out from Caitlin that Emily was a virgin. Stiles brings Scott to the hospital to show him that they're all virgin sacrifices.
In the locker room, Scott tells Stiles about the guy from the vet's office who disappeared. Stiles is more convinced that virgins are dying and declares that someone needs to sex him up right then. Danny offers, which Stiles finds sweet. They go on a cross-country run and find Kyle, the guy from the vet, sacrificed. Scott still doesn't believe that this is what's happening, but Stiles tries to convince him. While the Sheriff investigates the murder, Stiles goes to talk to Kyle's girlfriend to ask if he was a virgin. She slaps him but says no. Stiles then goes to talk to Lydia about his theory, but she's not interested in helping. He goes to talk to Deaton instead, convinced that he knows more than he says. Stiles explains what he knows about Druid and quickly realizes that he's not telling Deaton anything new. Lydia calls to report that their band teacher has gone missing, so Stiles and Deaton go to the school to investigate. They realize that it's soldiers who are being taken. In Mr. Harris's classroom, they find notes that tell them they are dealing with a Darach.
Stiles and the rest of the cross-country team are on a bus heading to a meet. Stiles is trying to quiz Scott on SAT words but Scott is having trouble because he's in pain. Stiles makes him show him what's wrong is horrified to learn that Scott isn't healing at all. He also notices that Ethan keeps checking his phone and pesters Danny to find out why. Danny doesn't want to but relents after Stiles won't give up. He reports that someone close to Ethan is dying. Stiles wants to stop the bus and ends up getting Jared to puke to do it. The bus pulls over, and he, Lydia, and Allison rush Scott into a bathroom to check his wound. Stiles and Lydia go to make sure the bus doesn't leave without them while Allison patches him up. Scott starts to recover and they all get back on the bus. Stiles and Lydia and discuss the darach.
The meet has been postponed, so they stay at the Motel Glen Capri for the night. Stiles and Scott discuss the possible culprits for the sacrifices. Stiles mentions Derek, twice, and Mr. Harris. He also lists Cora, Deaton, and Lydia. Stiles goes down to the vending machine and finds Boyd, who ignores him. He punches his way into the machine, and Stiles grabs some free food. Later, when he's brushing his teeth, he notes Scott acting weird, but Scott doesn't tell him what he's been seeing. Lydia and Allison then show up and tell them about the suicides. They start to look around and then hear a buzzsaw. They save Ethan from cutting himself with it. Stiles and Lydia find Boyd trying to drown himself and get a road flare so the heat of it will snap him out of the trance. They also use the flare to wake up Isaac.
They find Scott in the parking lot with a road flare of his own, having doused himself with gasoline. Scott believes that the best thing he can do for everyone is kill himself, but Stiles argues that Scott isn't nothing, that they're brothers, and that if Scott wants to kill himself he'll have to take Stiles with him. Stiles throws the road flare away. The darach sends it rolling back toward them, though, and Lydia tackles them all out of the way. They all spend the night on the bus instead of the haunted rooms.
Stiles shows up at the hospital with his dad to investigate the missing doctors. He thinks the darach is after healers now. He later reports to Scott that the dead ER doctor they found wasn't strangled but still died of asphyxiation. Scott gets a call from Deaton to inform him that he's going to be taken, so Stiles goes with Scott to the Animal Clinic. They're too late. The Sheriff is already there and wants to know everything. Scott convinces Stiles that they should tell his dad about the supernatural, but Morrell interrupts before they can. She suggests they use Lydia to find Deaton. Stiles and Cora get Lydia to try a series of divination techniques, but none of them work. Lydia then suggests talking to Danny, since his attempted murder doesn't fit the pattern. Stiles goes into Danny's room and looks through his bag. He finds a report on telluric currents and heads back to the Animal Clinic, where he meets up with Scott. The map from Danny's project and the map Scott got from Chris's desk line up, showing that sacrifices are made along current lines. They realize where Deaton has been taken, and Scott goes to rescue him while Stiles, Cora, and Lydia go to the Derek's loft to help him against Kali and the twins. They are able to turn the power back on in the loft, and arrive at Derek's apartment just after Boyd dies. Derek is distraught and Stiles puts a hand on his shoulder to comfort him.
Derek has been missing for two days, and Stiles goes to the loft to talk to Cora and Peter about where he might be. Cora explains to him that they were raised to hide and wait when threatened, so that's what Derek is doing. She wants to know why Stiles cares where he is, and Stiles explains that with all the people getting killed he thinks Derek should be doing something about since they all seem to be after him. Cora says that Derek is different from when she knew him, and Peter comes down to explain about Derek's history with Paige. He asks if Stiles knows why some Werewolf have blue eyes, and Stiles admits that he thought it was genetic. Peter's explanation is that it happens when you kill an innocent person. He tells them about Derek and Paige, the death of one of Ennis's Werewolf, their fight with the Argents, and Deucalion. Ennis declared a blood feud with the Argents. Stiles thinks they take revenge to an extreme, but Cora explains that pack members are more than just friends because the bond with pack increases their power.
They also explain about emissaries, and Stiles is incensed that no one told him his guidance counselor was working for the alpha pack. When Derek killed Paige out of mercy, it took a piece of his soul and turned his eyes blue. When Peter is done telling the story, Stiles admits to Cora that he doesn't believe him. He thinks there's a piece of the story missing and is willing to ask Derek about it if he has to.
Stiles and Scott go to the school because Lydia called them. She ended up there without intending to like the last time she found a body, only this time she hasn't found it yet. Scott finds Tara dead on the school sign. Stiles attempts to tell his dad that it's a sacrifice, but he doesn't listen. In English class, Jennifer talks about idioms and Stiles reveals that he and his dad play chess. Scott wants to talk to Ethan, and they decide the only way to get him away from Aiden is for Lydia to distract Aiden with sex. Stiles and Scott learn from Ethan that he and Aiden were the bottom of their pack and are the bottom of the alpha pack, too. Ethan confirms that Deucalion made his alphas kill their emissaries, too. They find Cora and Aiden fighting and pull them apart. Cora complains that they're not helping people, they're just finding bodies. She's hurt from the fight, so Stiles takes her home. While in the car, he gets a call from Allison who explains that the remaining sacrifices are philosophers and guardians. They think this means police officers and Stiles decides to tell his dad what's really going on. He takes Cora so she can wolf out as proof. Stiles uses a chess board to explain who all the players in the supernatural game are. His dad doesn't believe him. Cora is about to wolf out but passes out instead.
They take Cora to the hospital. Stiles still tries to convince his dad that what he's saying is real, but the Sheriff refuses to believe in anything he can't see. Stiles uses his dead mother as a trump card, but the Sheriff walks away. Stiles heads to the school where all the techers are going to be and helps Scott look for Lydia. They don't find her until Lydia screams. Both Scott and the Sheriff find Jennifer attempting to kill Lydia. Jennifer locks Stiles outside the room and takes his dad as a sacrifice.
Stiles and Scott go directly to Derek's loft to tell him that Jennifer is the darach. They wait for her to arrive and then accuse her. Stiles is crying when he asks her where his dad is. Scott reveals that she is the darach using mistletoe and Derek grabs her by the neck to kill her. Stiles and Scott beg him not to, and she argues that he needs her to save Cora. They drive to the hospital to see about Cora, and Stiles brings a bat. The hospital is being evacuated so they only have a certain window in which they can get her out. Derek, Jennifer, Stiles, and Scott go to Cora's room but find it empty. The twins have already shown up to take her, despite Peter's efforts to stop them. Derek and Scott take on the twins, while Stiles and Peter rush to get Cora. In the confusion, Jennifer escapes. They get Cora and run, but while they're running, Stiles decides to attack the twins with his bat. He breaks it over their head. They run some more and stop to try to form a plan. Stiles yells at Derek, getting his frustration out. Jennifer appears again promising to help with Cora and return Sheriff Stilinski if they keep her safe. Stiles tries to get her to prove her goodwill by healing Cora, but she refuses.
Deucalion demands that Jennifer be brought to him on threat of Melissa's life, but Scott doesn't think he's serious. They need to get Jennifer out of there. They all start looking for something to help distract the twins with. Stiles asks about the defibrillator but Derek asks him to put it down if he doesn't know how to use it. They find something and Peter and Scott take on the twins while Stiles, Derek, and Jennifer take Cora to the ambulance. Derek leaves Cora with Stiles, and Stiles touches his arm in reassurance. Stiles locks the truck up and waits. When he realizes Cora isn't breathing, he performs CPR and talks to her about how scared he is. Eventually Scott and Peter show up, and Stiles takes Peter into the ambulance, too. They wait until Isaac shows up with Chris Argent's car and transfer Cora. Stiles reads a medical sheet and realizes that guardian means parent and not police officer. He goes to find Scott and sees Derek unconscious in the elevator. Stiles leaves him for a second to follow Scott to the roof. He tries to get Scott to not go with Deucalion, but Scott is determined. Once they leave, Stiles goes back for Derek.
Stiles calls Derek's name desperately trying to wake him up. He's about to punch him in the face when Derek wakes up and grabs his wrist. Stiles explains about Cora and Scott and gets Derek out of there before the police show up. The police include Rafael McCall, who is apparently back in town. Stiles is not pleased to see him and avoids answering questions as much as possible but learns that someone wrote Argent on the elevator doors, indicating him as the last parent sacrifice. He goes to warn Chris and Allison, but Chris isn't that concerned. They decide to look for the parents in previous places that Jennifer had attempted sacrifices. Stiles is supposed to check with Lydia to see if she has any feelings. While they are at school, Stiles gets a message that Chris has been taken and starts to have a panic attack. Lydia calms him down by kissing him. She mentions the guidance counselor and he thinks Morrell can help. They go to her office and Stiles shows Lydia her file. It's full of her drawings of a tree. Stiles recognizes it as the root cellar of the nemeton and thinks Peter and Derek should be able to tell them where it is. Agent McCall stops Stiles to question him, so Lydia has to go to the loft on her own.
Stiles talks his way around Agent McCall to avoid giving him any information. Deaton ends up rescuing him and taking him back to the Animal Clinic, where he tells everyone his idea about surrogate sacrifices. Stiles and Deaton go to meet Scott in the woods to convince him to do it. He explains that they will die for a short while and then be brought back, which will give power to the nemeton. Scott agrees, and they all go to get an object that holds a lot of meaning. Stiles gets his dad's badge. Stiles tells Scott that his dad is back in town just in case he doesn't make it back alive.
Lydia holds Stiles under, and when he drowns he wakes up in the white room with the nemeton with Scott and Allison. When they touch the nemeton, they are each taken back to the woods. Stiles watches himself get caught by his dad when they were searching for the body in the woods. He backs up and bumps into the nemeton. When they wake up, it's 16 hours later but they know where the tree is. They split up. Stiles heads home to get a piece of his dad's clothing to bring to Scott so he can try to track him down. Scott, Allison, and Isaac get waylaid. On his way to the preserve, Stiles loses control of the car and hits a tree. He's knocked out for a while but comes to in time to find the nemeton and use his metal bat to keep the cellar from crushing everyone. When Deucalion defeats Jennifer and Derek and Scott kick Deucalion out of town, Stiles's life seems to return to normal, except for the darkness around his heart from the sacrifice.
Stiles has been having nightmares within nightmares. He wakes up in a locker and stumbles out into the school. He finds the nemeton in a classroom and goes to touch it, but when he does it grabs his arm. He wakes up into another dream where he's in bed with Lydia. She tries to calm him, but he realizes something is wrong because she shouldn't be there. He gets up to open the door in his room that's ajar and walks outside into the woods where he finds the nemeton again. He screams for himself to wake up, and wakes up peacefully to his dad sending him off to school. Stiles recounts his nightmares to Scott and only after he's in class with a teacher who is dead does he realize that he could be dreaming now. He wakes up screaming for real, and his dad runs in to hold him. When he leaves for school for real, Stiles notices that he can't read.
At school, Scott runs into Stiles as he's running from his shadow and they talk about the darkness they've been experiencing. Lydia and Allison join them, and Lydia gloats that she's not the only crazy person anymore. Stiles continues to have trouble reading. Scott starts to shift uncontrollably in the hallway, and Stiles ushers him into a classroom to hide him. They talk about how serious the situation is getting. Later, he goes to the sheriff station because it's either his mom's birthday or the anniversary of her funeral and they're going to put flowers on her grave. He sees his dad going through old case files with a new supernatural perspective. The Tate car crash is particularly plaguing him. Stiles learns that Agent McCall has also called an investigation down on his dad.
In class the next day, Stiles sees Coach and the whole classroom signing the same thing at him. He doesn't know what it means. When he runs away, he suddenly jerks awake in class, only Scott tells him he wasn't asleep. Everyone gathers at lunch to talk about the problem, and Kira shows up to suggest they're talking about bardo. Stiles and Scott then go to visit Deaton, who translates the sign language to "When is a door not a door." The riddle is solved with "when it's ajar" and he says their minds are open and need to be closed.
The Sheriff asks Scott and Stiles to help him with the Tate case and look for Malia's scent while he talks to the dad. Scott can't find anything because it's been so long. However, they decide to go searching in the woods on their own. They find the car wreck and a coyote with glowing eyes.
Stiles and Scott run around through the woods, and Stiles shows Scott Malia's den. They decide to ask the Sheriff to help find a missing person. They explain to him what they found, but he's skeptical that Malia is a werecoyote. They decide to try to look for her, and Stiles takes a doll he found in the car. At school, Stiles is asked to read in front of class, but the words slip off the page. He starts to have a panic attack, and Scott hurries him to the bathroom. Stiles starts telling himself that everything is just a dream, but Scott insists that it's real. Stiles reveals that you can tell if you're dreaming by counting your fingers. The police department shows up because the coyote attacked Kira on campus. Stiles tries to convince his dad that they're going to shoot a girl, but his dad still doesn't buy into the supernatural. It takes a demonstration of Scott's superhearing to remind him that it's all real.
Isaac, Scott, and Stiles go to Deaton to get some tranquilizer. Scott thinks he can make Malia shift like Deucalion did to him, but only if he wasn't afraid of shifting. Stiles comments that they need a real alpha, by which he means Derek. They end up asking the twins for help and go to Derek's loft. The twins beat Scott up but it doesn't help him shift. Everyone meets at the preserve to find Malia. When Scott, Allison, and Isaac take off after Malia, Lydia steps in a steel jaw trap. Stiles disarms the trap without being able to read the instructions. He rides with his dad when they return a human Malia to her father.
Stiles is at the school setting up that year's Mischief Night prank on Coach. He calls Scott in to help and they spend all night at it. The next morning the twins try to get Scott to let them join his pack, and he refuses, which Stiles supports. He notices Scott's interest in Kira and encourages him to go get her. He also finds an extra key on his keyring. The police show up at school again, this time because Barrow was spotted near campus. Stiles learns from his dad that Barrow killed kids with glowing eyes. He thinks Barrow is still on campus and tries to get his dad to stop from pulling his men back, but there's no evidence to suggest they should stay. Stiles and Lydia team up and start looking for clues. Scott and Isaac team up. And Ethan and Aiden team up, and they all start looking. When Stiles and Lydia spot a picture of an explosion, they realize that Barrow could blow up the whole school and pull the fire alarm to get everyone out.
Stiles gets detention, and then he and Lydia go back to his house. He explains to her how his case wall and string work, while she apologizes for getting him in trouble. He is adamant that he believes in her and her powers. They go back to the school to look around more and find evidence of Barrow in the chemical lab closet. When they come out, they see numbers on the board that spell out Kira's name. This tells them who the next victim is going to be. They rush to Kira's house but are too late to keep her from getting taken. Stiles figures out that the buzzing Lydia has been hearing could be from the power station, so they head there. Scott and Stiles both run in. Stiles brings his bat and gets hit with electricity when Barrow blows up the station, although this isn't revealed until later.
Stiles, Scott, Lydia, and Kira get questioned by Agent McCall. Stiles deflects the questions through his normal obfuscation and they are let go. Stiles is much less trusting of Kira now that they know she's supernatural, and he tries to steer Scott away from her. Scott and Kira ask Stiles for his help in getting her phone out of the evidence at the station. They lie to him and tell him that there are naked photos on the phone, when really they are photos of Kira's kitsune aura. He gives them keycards to get in and then later distracts Agent McCall by talking about the case and then threatening to reveal the secret that McCall hasn't told Scott. He follows them to the black light party at Derek's loft and runs into Caitlin who pulls him onto the dance floor. She doesn't recognize him, but he knows her as the girl whose girlfriend was killed. When they sit together, Caitlin explains that she's bisexual and asks Stiles if he likes boys. He gives her a surprised look but doesn't answer. The extra key on his keyring is glowing because it has phosphors on it, which means he's been handling chemicals. Stiles leaves the party and goes back to the chemical lab at school. He writes the numbers that were on the chalkboard next to the ones that were already there and proves that it was his handwriting.
At school, Stiles explains to Scott about the key and his handwriting on the black board, but all the evidence is gone. He thinks he's the one who helped Barrow, but Scott doesn't believe him. Stiles takes himself to the hospital on the edge of tears. He talks to Melissa, and she takes down his symptoms. She decides he just needs to sleep and gives him a sedative. As he goes to sleep, he calls her mom. At night, he wakes up and starts wandering the hallways of the hospital. He ends up in a dark room, and the Oni appear around him. They reach for him, but he grabs one by the hand and plunges his fist into its chest. He pulls out a firefly, and the Oni disappears. This is the first appearance of the nogitsune in Stiles. When Scott finds him, the nogitsune hides again and Stiles acts like his normal self.
Stiles calls Scott in the middle of the night, afraid and not sure where he is. He begs Scott not to tell his dad and worry him, but that he needs him to come find him. Stiles tells him that he's in a basement, he's bleeding, and he thinks there's someone in there with him. Before he left home, he rearranged the case board on his wall, tying all the strings to a pair of scissors and stabbing them into his bed. Lydia, Aiden, Scott, and Isaac find this, and it leads Lydia to think Stiles is at Eichen House. Meanwhile, Stiles is in the basement with a steel jaw trap on his leg. He uses his phone as a flashlight and sees the Bandaged Man there with him, writing the onore kanji on the wall. Stiles struggles to get the trap off and screams at the Bandaged Man, who replies in Japanese. The trap switches to Stiles's other leg as the Bandaged Man tries to show him that he's in a dream. He claims he's trying to save them. He asks Stiles a series of riddles, but Stiles can't answer the last one and Bandages screams in his face. He comes out of the dream as Agent McCall and Melissa pull him out of the coyote den.
They take him to the hospital. When Stiles recovers from exposure, they decide to give him a brain scan because his symptoms match his mom's. Scott goes into the MRI to talk to him and promises that if the test shows he's sick, he'll do something. It sounds like a promise to turn Stiles to save him. They hug. As the scan starts, Stiles becomes upset. He enters a dream with the nogitsune who asks him the riddle again. He doesn't know, but the nogitsune scares him by threatening his family. When Bandages takes off his wrappings, Stiles can see that it is himself. When he wakes up, the cut power line on the hospital roof explodes, and the nogitsune has control of Stiles's body. He leaves, but has a confrontation with Ken Yukimura and her Oni.
The nogitsune leaves the hospital and goes missing for two days. The next time anyone sees him, he's in the basement of the high school. Ethan and Aiden attack him, but Scott makes them stop. Stiles admits that he doesn't know what he's been doing the last two days but has a bag of gear to show them. They realize from the items that he collected some steel jaw traps from around the Tates' house and put them in the preserve where the cross-country team runs. They had out to stop all the students from running. Stiles digs up a chain on the ground but it isn't attached to anything. Coach then hits a trip wire that shoots him with an arrow. While he's down, Scott takes his pain. They realize that there are the makings of another bomb in Stiles's Jeep and then further that the bomb threat the school is a false alarm. The sheriff station is the real target. They arrive after the explosion, and Stiles asks Scott to take the pain of a dying man.
As night falls, they have to get Stiles to some place safe, so Scott and Kira take him to the Animal Clinic. They don't make it in time and have to fight off the Oni and Scott gets stabbed. Once they get inside, Stiles reveals himself to be the nogitsune. He plays with the sword stuck in Scott and explains how he's been playing him all day getting him to absorb pain. The nogitsune then draws all the collected pain out of Scott and Deaton shows up and drugs him with letharia vulpina.
Stiles has asked his dad to put him in Eichen House while he goes to LA to see a specialist about the brain scans. Scott tries to stop him from going in, but Stiles insists. Inside, Stiles witnesses a patient commit suicide. His roommate also has to be tied down to his bed. Stiles doesn't sleep at all because he didn't bring his pillow. He wants to call his dad to get himself released. Oliver takes him to the pay phone, but it doesn't work. While he's walking around, he overhears Meredith Walker talking in a way that suggests she knows who he is. He also runs into Malia, who punches him for having helped turn her back into a girl. While he's down, he looks down into the basement, which he recognizes from his dreams. Morrell shows up and takes him to group therapy. Stiles is nervous during therapy while they talk about guilt. He keeps touching his neck. Morrell notices and cuts the session short. The lines on his neck are a Lichtenberg figure which only showed up after the letharia vulpina injection. Once the lines fade the nogitsune will come back. Morrell threatens to kill him if the nogitsune takes over.
Stiles tries to find a way into the basement. He needs a key that only Brunski has. He goes to take his pills in the bathroom but finds Malia in there showering. She's always cold now that she doesn't have fur and is unconcerned about him seeing her naked. They talk about how much Malia's life sucks and she blames him for it. Oliver and Malia cause a distraction so Malia can steal the keys for Stiles. He gets caught trying to get in the room and gets put in solidary and sedated. Bandaged Man shows up in his dreams demanding to be let in. Stiles wakes up screaming to find Malia in the room. She has another way to get into the basement. They find the onore kanji on the wall and start going through records. They don't find anything and end up having sex on the couch. Afterward, Malia has an idea and breaks the wall with the kanji. They find Rhys's body in the wall with a photo of Ken Yukimura. Oliver then appears and tasers Stiles and Malia and drugs her. He threatens Malia with a drill until Stiles agrees to let the nogitsune in. The nogitsune knocks Oliver out and escapes Eichen House.
The nogitsune goes to the high school to threaten Ken Yukimura. He wants Noshiko's Tails. When Ken Yukimura won't tell him, he chokes him with a fly. He then goes to Stiles's room and sets off the security system, so everyone will go there to look for him. Either the nogitsune or Stiles rearranges the pieces on Stiles's chess board to leave a message. They mark Derek as the king on the board, which leads the Sheriff to conclude that they need to go to Derek's loft. He thinks they can outfox the fox because they know they're walking into a trap. The nogitsune is waiting for them in the loft.
The Sheriff asks Stiles to put the handcuffs on, and the nogitsune lets him only to prove a second later that Stiles is not in control. They try to taser him and attack him, but nothing works. Chris ends up drawing a gun on him, which gets the Sheriff upset. The nogitsune enjoys all their strife. His plan was to have these people who would protect Stiles around when the Oni showed up. They fight the Oni for a little bit, and then both the Oni and nogitsune vanish. It travels to Eichen House where Noshiko is with her last Tails. The nogitsune takes it and uses it to slice itself open, releasing flies. The flies turn Ethan, Isaac, and Derek into puppets. It then dumps Stiles's injured body in a parking lot for Lydia to find. They bring him to Scott's house, where Deaton drugs him with kanima venom in the hopes of keeping him restrained. The nogitsune is able to taunt them, though, until they tape his mouth. Peter arrives to advise on giving Stiles the Bite, but he thinks they should do a mind meld instead and pull Stiles to the surface. The nogitsune is intrigued by this and can't stop them.
Inside Stiles's mind, Scott and Lydia have to pass some tests before find Stiles and the Bandaged Man on the nemeton playing Go. Scott roars to get Stiles's attention, and Stiles dashes the game away. When they all leave the mind meld, the nogitsune vomits up bandages and eventually a bandaged figure crawls out of the floor. It turns out to be the real Stiles. While everyone is checking on him, the nogitsune escapes with Lydia.
Melissa checks on Stiles's health, which seems okay. He wants the Oni to test him to be sure that he's himself. Scott is against it, but Stiles insists. The Oni confirm that he's himself, and Scott takes Stiles to see his dad. They hug and get down to trying to find Lydia. They don't know what the nogitsune could want with a banshee. Stiles thinks they should ask another banshee, remembering Meredith Walker at Eichen House. The Sheriff goes to get her. While he's gone, Stiles goes back to Scott's house and accidentally falls asleep. When he wakes up he starts to have a panic attack, but Scott calms him down. Stiles can't get warm, and he hurts everywhere. Scott notices when he touches him and starts siphoning pain. Stiles won't tell him how much it really hurts. Kira calls Scott to tell him that Meredith Walker is at the school, so he and Stiles head over there. They pick up Meredith and bring her back to Scott's house. They have to make some excuses to get away from Scott's dad, and Meredith insists that she likes Isaac better than Stiles, so he comes upstairs with them.
Stiles tries to figure out how to get information out of Meredith. Eventually she asks them if they're going to answer the phone, and Stiles hands her his phone. The voices tell her coup de foudre, which Scott recognizes from Noshiko's story. It leads them to Oak Creek. Stiles looks sicker by the second. They don't know what kind of tie still exists between Stiles and the nogitsune, but Stiles doesn't care. If killing it kills him, then that's what he'll do. When they get there, Stiles and Scott go to search for Lydia while everyone else fights the Oni that the nogitsune stole from Noshiko. On the way out, Stiles collapses, and Lydia stays with him.
Following Allison's death, Kira and Noshiko take Stiles home with them. Noshiko explains that they need a divine move in order to win the game now: a move so unexpected that it changes the tide. Scott, Stiles, Kira, and Lydia come up with a plan and go to the school. Whatever they're planning may kill Stiles, too, but he doesn't care. As soon as they walk in, they're transported to the Japanese garden where the nogitsune was attacked by Oni. The Bandaged Man promises to kill all of Stiles's friends unless he kills himself. Scott and Kira try to fight the Oni off. Kira loses her sword and Stiles grabs it, holding it to his stomach. He considers killing himself but sees the classroom they're standing in in the reflection in the sword. He tells Scott that everything is an illusion, so they can walk out without being hurt. Scott believes him and walks the gauntlet. They emerge into the school and find the nogitsune waiting for them. Scott bites the nogitsune, turning him into a fox and a wolf and Kira runs him through the katana, killing him. After the nogitsune dies, Stiles faints. When he wakes up, he asks if they're all alive, momentarily forgetting Allison. Lydia feels another death close-by and runs outside to see Aiden dying. Stiles holds her while she cries.
Stiles and Scott start teaching Malia how to control her powers. Stiles also takes down his case wall. When Derek is shot by Kate, he pictures Stiles in a dream and talks to him about what's happening and how afraid he is. Stiles tells him how to judge if he's in a dream, and Derek grabs his hand and counts his fingers. Derek realizes the conversation with Stiles is a dream and comes back to reality to face Kate.