Supernatural: Season 8, Episode 15 - ProjectFreeTV

8 - 15: Man's Best Friend with Benefits

Police officer named Kevin, who turned to witchcraft after working a case with Sam and Dean, is plagued by nightmares in which he murders innocent people. However, when the murders actually happen, Sam and Dean are called in by Kevin's "familiar" to help -- but the brothers aren't sure they want to save a witch.