Sam, Dean and Castiel are thrown into an epic battle. Meanwhile, Jack becomes disenchanted with all the lies, and an old friend from the past shows up.

Sam finds a clue to Dean’s whereabouts, so he, Mary and Bobby set out to investigate. Castiel imparts some sage advice on Jack, who, still desperate to belong, seeks out…

Sam and Dean investigate a murder and find Garth is already on the case. Dean is not happy to learn that Garth has assumed Bobby’s duties, but Garth points out…

Sam has a vision of Dean shooting a defenseless man, and they go to the town of River Grove, where they find the townspeople have been possessed by a virus…