Chris begins Allison's training to become a werewolf hunter. At school, Erica, an epileptic girl, has a seizure and ends up in the hospital. There, Derek delivers the bite upon the promise that her illness will vanish. Dr. Deaton finds a dead hunter in his office and Chris wants him to find out what happened. Scott discovers Boyd is now a werewolf and is forced into a fight with Derek, Erica, and Isaac. Jackson is shocked when he exhibits inhuman strength.