Scott and his friends are on the hunt for an important Japanese artifact.
Stiles checks himself into Eichen House, the same institution where Barrow was committed. Immediately upon his arrival someone hangs themselves.
Immediately after entering "Echo House" Stiles wants to leave.
Stiles finds Malia is locked up with him there as well.
Ms. Morell is working at the hospital.
Argent and Derek are in jail. Derek learns the Katachi investigation is now a federal case and they're taking all of his evidence away. Argent compares the Nogitsune inhabiting Stiles to the Bezerkers.
Morell gives Stiles amphetamines so he can stay awake so the Nogitsune won't take over. She has the drug they use for lethal injection on hand to use in case he is not rescued by the time the lichen wears off.
Stiles walks in on Malia showering in the boys locker room. She's unhappy that they invaded her home and forced her into being a human. Stiles says he knows somebody who can help her change if she'll help him get into the basement.
Scott, Lydia, Allison and the twins decide to rob an armored vehicle to get the Katashi evidence.
Stiles gets caught trying to go into the basement with the amphetamines on him. They inject him with haldol.
Kira shows Scott how she's learning how to use a sword.
Stiles is terrorized by the Nogitsune who is trying to get in, but Malia comes to his aid.
Araya the werewolf hunter is back acting as Argent's lawyer to try to get information.
Malia and Scott connect and make love.
Scott uses his true alpha sense to get the scroll off of Kincaid.
Malia and Stiles find the body of the Nogitsune in the basement of Eichen House and there is evidence to deliver to Scott. Before they can do it, the other patient, Oliver, stuns them and binds them. The Nogitsune has entered Oliver's brain and is intent on drilling into Malia unless he lets Stiles in.
Stiles falls asleep immediately and lets in the Nogitsune. He punches out Oliver and leaves.
Deaton tells Scott the information on his scroll says one way to rid Stiles of the Nogitsune is to change his body. Scott says he knows of a way to do that: turn Stiles into a werewolf.
Malia leaves Eichen House to find Scott McCall.