Peter is attacked and injured by the Mute at his loft. Scott and his friends attempt to plan a way to help Liam deal with the upcoming full moon. Deputy Parrish, Sheriff Stilinski and Derek discover that the Mute is an assassin hired by someone called the Benefactor. Scott and his friends lock up Liam and Malia at Lydia's lake house; unfortunately, Liam texted his friends that there was a party at the house, and many students show up as a result. Lydia deals with the party, and discovers a soundproofed room in her house that seems to trigger her banshee powers. Derek and Sheriff Stilinski locate the Mute at the high school, and avoid an explosive device known as a claymore mine that the Mute planted; the Mute then attacks them directly, but Derek is able to subdue him. However, Peter then appears and kills the Mute. Stiles is able to help Malia gain control over her shift; meanwhile, Liam escapes, but Scott is able to subdue him with help from Chris Argent. At the party, a werewolf is killed by Violet, who is revealed to be one of the agents of the Benefactor, along with her boyfriend Garrett. Lydia manages to decipher the code in the Mute's computer (using the keyword "ALLISON"), which reveals that it's actually a "dead pool"-a hit list of supernatural beings living in Beacon Hills, which includes all of their supernatural friends.