The secret behind Derek's tattoo is revealed and the Alpha pack make their presence known. Derek and Isaac struggle to locate Erica and Boyd.

Trapped inside an evacuated Beacon Hills hospital by a powerful storm, Scott and Derek must defend themselves against the Alphas while trying to figure out how to save Cora’s life.

On the night before Halloween, Mischief Night, a convicted murderer brought to Beacon Hills Hospital for surgery escapes, forcing Scott and his friends to step in to help when his unexpected target becomes clear.

Stiles goes missing; Scott and the others set off on a search; Lydia tries to master her new abilities.

An assassin targets Scott and Liam at the lacrosse team's annual bonfire.

Scott and Kira fight to protect Satomi's pack from assassins.