|“|| Valack: "How many have died so far? All of them teenagers.... Am I right? Want to know how many died the first time they came here? Wonder how many will die if they succeed?"|
Lydia: "This did happen before."
Valack: "And now they're back. All because a few teenagers who never even considered the consequences decided to reignite a supernatural force they barely understand."
Lydia: "The Nemeton."
Donovan, who is revealed as a Wendigo-Lamprey Chimera, chases Stiles into the school library and threatens his life by stating that he will eat Stiles' legs. Stiles attempts to escape Donovan's grasp by climbing up a construction scaffolding, and when he tries to break his hold by dropping a large amount of metal braces onto Donovan, he accidentally kills the Chimera when one of the braces impales him in the torso. Stiles rushes to the Jeep to figure out his next move, where he becomes confused when the police arrive and leave in minutes. When he returns to the library, he finds that Donovan's body is gone and that somehow, all evidence of his death has been cleaned up, with the exception of a single drop of blood on one of the metal braces on the scaffolding.
Scott and Kira are asleep in Scott's bed, where Scott overhears Kira muttering "Watashi wa shi no shisha da!", which, unbeknownst to him, is Japanese for "I am the Messenger of Death" and is the same thing she shouted at Sinema the night before, causing him to become worried about her current behavior. Just then, Scott's phone rings, revealing that the alarm for the animal clinic has been set off. It is then revealed that Parrish has stolen the bodies of Tracy and Donovan from the clinic and the library and has brought them into the woods in another trance before setting them on the Nemeton.
The next day, Malia brings the book that she found in Tracy's room about the Dread Doctors to school, where she shares it with the rest of the pack. After Scott and Kira made enough copies of the book for all of them, Lydia began examining the book in class, where she recognizes a name in the acknowledgements page-- Gabriel Valack, a three-eyed inmate of Eichen House. The pack decides they needed to speak with Valack to learn more about the Doctors. Scott, Kira, Stiles, and Lydia go to Eichen House, where Dr. Conrad Fenris, the facility's medical director, reluctantly allows them to speak with Valack as a favor to Deaton. However, due to the mountain ash in the building's foundation, only Stiles and Lydia are able to make it to Valack's cell, forcing Scott and Kira to wait for them outside the closed unit.
On the way to Valack's cell, Stiles makes eye contact with a Sluagh who takes the appearance of Donovan, which clearly rattles him to the point where even Valack questions him on what he saw when he looked at the creature, since the Sluagh takes the form of recently-departed souls which have become inextricably linked to it. Stiles and Lydia then show Valack the book, where the three-eyed human informs them that he was indeed the author and used the name T.R. McCammon as his pen name in order to detail the first time the Dread Doctors came to Beacon Hills.
Valack then informs them that his information comes at a price-- he wants to record Lydia's Banshee scream, a deal to which Lydia reluctantly agrees against Stiles' protests. Valack goes on to say that the Dread Doctors gave themselves powers based in electromagnetic forces, which they have then used to gain electrokinesis, electromagnetokinesis, memory manipulation, and extended lifespans. He then chastises the two for involving themselves in the surrogate sacrifice ritual that reawakened the Nemeton, which he refers to as a "supernatural force that they barely understand" before implying that it was this ritual that drew the Doctors to their town. He also reveals that he had a good career as a physician until the Dread Doctors caused him to lose his professional reputation and livelihood due to no one else believing that the Doctors existed.
While Scott and Kira talk outside of the closed unit, Kira's Kitsune powers start to go haywire, causing her to involuntarily discharge foxfire that affects the entire power grid in the facility, causing the lights to flicker and explode. Scott begs her to stop what she's doing, but Kira, panicked, exclaims that she has no control over her electrokinesis and that it's happening against her will. In the closed unit, Valack, noticing the electrical failure, frantically informs them that Kira's unstable Kitsune powers have disabled the telluric currents that, in conjunction with the mountain ash built into the building, act as Eichen House's supernatural protection and that bringing Kira there essentially opened the door to allow the Dread Doctors inside. Fenris finds Scott in the hallway kneeling next to the now-unconscious Kira, who is still discharging her blue foxfire in large amounts; though Fenris advises Scott to leave her behind before so they can both run for their lives, Scott refuses to leave without her.
After Fenris leaves Scott and Kira to save himself, Scott musters up the strength to carry Kira outside the building, despite the electrocution from her foxfire weakening him with every step. The two collapse on the ground at the bottom of the front steps, where Scott assured her that he meant it when he said he loved her the previous night. Meanwhile, Stiles and Lydia hide in the nearby shower room, where they lament the fact that, based on Valack's statements, everything that has happened since the surrogate sacrifice ritual is not only their fault, but their responsibility to fix. The Doctors enter the asylum, use their powers to unlock Valack's cell, and take out a cylindrical surgical device to remove his third eye. Afterward, the injured Valack uses a styrofoam cup and his audio recorder with Lydia's Banshee scream to break the glass in his cell and escape.
Elsewhere, Malia is in the library, reading The Dread Doctors novel and highlighting the relevant sections when Theo Raeken approaches her and asks her about what she is doing. After the two study a little longer, Theo remarks that he saw Malia's most recent disastrous driving lesson with Mr. Yukimura and offers to give her a lesson of his own in his truck. While they drive, Malia becomes overwhelmed by flashback-hallucinations of her repressed memories of the car crash that killed her adoptive mother, Evelyn, and her adoptive sister, Kylie. While she originally under the impression that it was her unexpected first Werecoyote transformation on the full moon that caused the car crash that killed Evelyn and Kylie nearly ten years ago, it was really Malia's biological mother, the Desert Wolf, who shot at the car in an attempt to kill Malia and caused Evelyn to drive off of the road and into the nature preserve. Seeing Malia is in a trance, Theo manages to get her to stop the car before her unconscious speeding could cause them to wreck, but as soon as they do, he is forced to get out and tackle Malia out of the way after she collapses on the road in front of oncoming traffic. When Theo asks her what happened, all Malia can say is "It was her-- the Desert Wolf."
- Tyler Posey as Scott McCall
- Dylan O'Brien as Stiles Stilinski
- Holland Roden as Lydia Martin
- Shelley Hennig as Malia Tate
- Arden Cho as Kira Yukimura
- Dylan Sprayberry as Liam Dunbar (credit only)
- Ryan Kelley as Deputy Jordan Parrish (uncredited)
- Cody Christian as Theo Raeken
- Ashton Moio as Donovan Donati
- Steven Brand as Dr. Gabriel Valack
- John Posey as Dr. Conrad Fenris
- Benita Robledo as Deputy Valerie Clarke (voice only)
- Marti Martulis as The Surgeon
- Douglas Tait as The Pathologist
- Caitlin Dechelle as The Geneticist
- Clayton Froning as Schrader
- The title is a reference to The Dread Doctors novel and its author, Gabriel Valack's involvement with the Dread Doctors.
- Valack lost his third eye to the Dread Doctors, which presumably caused him to lose at least some of his ESP abilities.
- It was revealed that most of Donovan Donati's animosity toward Sheriff Stilinski is because his father was Sheriff's partner back when he was still a deputy, and he blames Sheriff for leaving to call for backup while his father went into the house of a suspect who shot him in the spine and paralyzed him from the waist-down.
- Donovan Donati - impaled through the chest; killed by Stiles Stilinski
- Eichen House Orderly - stabbed through the back; killed by the Dread Doctors
- Beacon Hills High School
- Parking Lot
- Ms. Flemming's Classroom
- McCall House
- Scott's Bedroom
- Stilinski House
- Stiles' Bedroom
- Beacon Hills Preserve
- Dread Doctors' Operating Theater
- Eichen House
- Closed Unit
- Valack's Cell
- Closed Unit
- "Thinkin' of U" by Summer Heart
- Lydia and Malia discuss The Dread Doctors novel in the hallway while Kira and Scott print off a half-dozen copies of the book for the pack.
- "Strange Entity" by Oscar and the Wolf
- Theo studies with Malia at the library and offers her a driving lesson in his truck.
- "Eyes Closed" by Hermitude
- Malia drives Theo's truck while he rides shotgun, and Malia is suddenly stricken by a flashback-hallucination caused by the book.
- "Until We Go Down" by Ruelle
- Scott, struggling to stay upright as Kira's foxfire shocks up, carries Kira out of Eichen House to save both of their lives. Kira brings up Scott telling her he loves her in the previous episode, and Scott assures her that he meant it.