Scott, Stiles, and Allison suffer side effects from the ritual sacrifice; Sheriff Stilinski searches through some old cases.

Cast: Tyler Posey, Crystal Reed, Dylan O'Brien, Tyler Hoechlin, Holland Roden, Jill Wagner, Orny Adams, Linden Ashby, Ian Bohen, JR Bourne, Arden Cho, Tom Choi, Matthew Del Negro, Gideon Emery, Melissa Ponzio