The Oni, under the control of the Nogitsune, systematically and violently take control of the hospital, Sheriff's station, high school and Alan's animal clinic. Isaac and Mr. Argent realize that silver can actually destroy the Oni. Everyone shows signs of the poisoning seen in others attacked by the Oni. But Scott, Kira, Stiles and Lydia defeat the Nogitsune by realizing the attacks are an illusion. Scott bites the Nogitsune, following the instructions on the scroll stating that it cannot be both a fox and a wolf. The duplicate of Stiles that the Nogitsune was using as a body disintegrates, and Isaac traps the Nogitsune in a box made of Nemeton wood. Lydia then gets a feeling and runs outside to find that Aiden has been stabbed and now is lying dead in the arms of Ethan, his twin brother. Later, the injured people start healing and all seems well again in Beacon Hills. In a series of flashbacks, it is revealed that Kate Argent, whose throat was torn out by Peter's claws, is shown to be alive and is a supernatural being.