Scott sits on a bench at the police station next to Lydia and Isaac. He remembers Allison's death and rehearses his story with Argent. Scott doesn't understand how Argent can remain so calm but he says that it's what they do. At the station, Isaac gives his statement and says it happened so fast.
Noshiko gives Stiles some tea at her house. Yukimura doesn't think it's safe for Stiles there. Kira reminds them that Allison killed an Oni but Stiles says that she died right after that. Yukimura says Stiles needs to pull out a divine move to beat the nogitsune. Noshiko buried it in the Nemeton which kept it trapped for so long. She doesn't know much about the Nemeton but Stiles says Deaton does.
Argent returns home with Isaac. He says he'll be fine because has an ability to compartmentalize his emotions. Isaac says he doesn't and they hug.
Stilinski tells Parrish that he wants to keep Allison's death quiet as long as they can. Parrish pulls his gun out when he sees one of the Oni attack an officer and fires several times at them.
Derek uses a lighter to heal the Twins of their wolfsbane injuries. He doesn't want them to hide and suggests they can join Scott by fighting for his cause. Scott will do anything he can to protect those he loves.
Deaton tells Scott and Lydia about the nogitsune that they are fighting. The Nemeton no longer has the same power to hold the nogitsune and Scott asks if there's anything else that they can use. Deaton says there are some powerful objects that are housed in the Nemeton's wood. Lydia asks if Talia Hale's alpha claws were held in a Nemeton box and Deaton says they were because he made the box.
At the hospital, Stiles asks a nurse to page Melissa. However, one of his Oni stab the nurse before he can call. The lights flash and everyone runs as the Oni kill anyone in the hallway.
Stilinski looks out of his office at the downed Oni. He watches as it stands up and enters the office. The officers inside fire everything they have at the Oni and Stilinski grabs a shotgun and fires at the creatures. He hits one before the other slashes his arm. The Oni advance on the officers.
Melissa and Kyle walk through the hospital discussing Scott. They get in an elevator that brings them to the floor with the Oni. One slashes Melissa's leg as Kyle fights them off and shuts the door.
Isaac tells Argent that Allison was trying to say something as she died. She wanted to tell Argent something but wasn't able to finish the sentence. Argent mentions the silver arrowhead she was making and Isaac insists that he see it. He has a feeling it isn't where she left it.
Kyle bandages Melissa's leg as the lights continue to flicker.
At Deaton's, Lydia almost passes out when she feels like they are running out of time. Kira helps Stiles into the room and he says he had the same feeling.
Argent shows Isaac the arrowheads and asks why she made four. Isaac explains there must have been five because she killed an Oni with one. The bullet Argent used against an Oni so long ago was also silver. However, it went straight through and didn't kill it. Isaac suggests silver is like a poison to the Oni and it needs to stay in the body, and thinks that was what Allison was trying to say as she died.
At the police station, Parrish wonders why the Oni left and let them live. Stilinski isn't sure they're in the clear because black mist is flowing out of their wounds.
Scott, Stiles, Kira, and Lydia arrive at the school. Stiles asks them to carry through with the plan, even if it kills him. They enter the school and find themselves in a snow-covered Japanese garden.
In the elevator, Melissa tells Kyle to try again with Scott. Kyle promises to make things work between them. The door opens and the Oni are gone.
Outside of the school, Derek and the Twins approach the nogitsune and two of its Oni. He's no longer an alpha but promises that he can fight like one. He puts down the box that contains Talia's claws.
Oni attack Deaton in his office. They slash him across the chest and then disappear.
In the garden, the nogitsune walks toward Scott and his group. The nogitsune says that it promised to kill all of them one by one. Three Oni appear, ready to fight. The nogitsune says that they are between life and death in this garden, and warns that everyone Stiles cares about is also dying. The nogitsune claims to have won all of the territories in their game, explains seppuku, and declares that Scott will be the one to kill Stiles. It then says that everyone touched by an Oni's blade will die unless Scott kills Stiles first. He's doing this to win their game.
Stilinski tries to keep Parrish awake. Whatever was on the blade is working fast on them.
Melissa explains that she sent Kyle away because he was a drunk. He is there to make it up to both her and Scott. Kyle notices blood on Melissa's mouth and tries to call someone to help.
Kira and Scott fight the Oni as Lydia and Stiles watch from the sidelines. Scott doesn't understand how they're in this place.
Derek and the Twins fight off the Oni. They suspect Scott is somewhere nearby and Derek says he's in the school. He then tells one of the Twins to get to the box.
Stiles grabs Kira's sword and prepares to stab himself. The nogitsune tells him it's the only move left. In the reflection of the sword, Stiles sees a textbook and desk in the snow nearby. He gives the sword back to Kira and says he has a divine move left.
The Twins don't think they can beat the Oni and tell Derek to take the box. Argent arrives and shoots an Oni with a silver arrow. It explodes and Nogitsune Stiles runs away. Derek yells for Isaac to get the box to Scott.
In the garden, Stiles tells Scott to stop fighting the Oni because it's only an illusion. They are all sliced by the Oni but keep walking toward the nogitsune. Scott pushes the nogitsune through the garden door and they find themselves back in the school. Nogitsune Stiles attacks them and says they can't beat him at his own game.
Argent finishes off another Oni before the last one cuts an arrow in half. Aidan grabs the arrow and stabs the remaining Oni with it. He looks down to see a sword sticking out of him.
Nogitsune Stiles warns Lydia and Stiles that he can't be killed. They remind him of their only solution, to change the nogitsune from a fox to a wolf. Scott bites the demon right before Kira thrusts her sword through it. The nogitsune falls to the ground and a fly emerges from his mouth. Isaac catches it in Derek's box, while Nogitsune Stiles collapses to dust on the ground.
In the hospital, Melissa wakes up to find her leg wound healed. Deaton and the police officers are also healed.
Stiles falls to the ground and wakes up surrounded by his friends. Lydia looks to the door. Outside everyone gathers around the dying Aidan. He says that Lydia never believed he was one of the good guys anyway but Derek says she'll believe him. Lydia runs outside toward the group and sees Aidan die in Ethan's arms. She turns around and hugs Stiles.
Noshiko and Yukimura put away the game that Stiles and the nogitsune were playing.
Melissa hugs Scott at the kitchen table. Isaac carries the nogitsune box out of Argent's apartment.
At school, Kira tells Lydia that she wishes there were something she could do. She doesn't know how much space or time to give everyone. She still feels like the new girl at school. Lydia says she won't be for long when she sees Malia walk by.
Scott and Stiles work to try to help Malia reveal her claws at will.
Danny and Ethan break up at school. He doesn't think he can date a werewolf. Ethan is shocked that Danny even knew that about him. They kiss goodbye one final time.
Stilinski walks in on Stiles cleaning his room. He says he's just clearing his head after all that has happened.
Deaton tells Scott that things will always even out. No matter how good or bad things get, they will always return to normal.
Derek tells Stiles about a dream he had. In the nightmare, hunters broke into his loft. He tells of the leader Severo who asked where the she-wolf was. Derek warns him that he would never find Cora but that's not who Severo is after. A smoke bomb goes off and Derek hears growls. The hunters were all taken out by a werewolf. The werewolf shot him in the chest with a shotgun. He wonders if someone could be turned into a werewolf by just a deep scratch. Derek says he never woke up and Stiles says he can tell if he's awake by the number of fingers he has. Stiles holds his hand up and he has six fingers. Derek slumps down with a shotgun wound and realizes that it's real. He looks up to see that Kate Argent was the one who shot him. She says if he's surprised now, he'll be even more shocked when she reveals a secret to him. Kate growls and shows that she's now a werewolf.