As Scott's second full moon approaches, he gives in to his animal urges and hurts Stiles, but Stiles gets a measure of revenge in locking him up. Meanwhile, Jackson continues to try and get closer to Allison. The Argents learn that Scott somehow knew Derek.

The Alpha finally reveals himself to Scott and gives him an idea of why he has killed certain people. Argent stages an encounter thinking that Jackson may be a werewolf. Meanwhile, Allison discovers a bit more about her family's secrets and confronts Lydia about her kissing Scott.