One such threat is the appearance of a very powerful witch named Rowena, who also turns out to be Crowley's mother and has the power to kill demons. As the season progresses, all-new threats emerge to once again push all of our heroes to their limits. As Sam continues to cure Dean, he eventually escapes the devil's trap and tries to kill Sam but Castiel arrives, overpowers Dean and they continue curing him until he is finally human. Castiel and Hannah are on the way to help but are delayed because of a rogue angel who injures Cass and tortures Hannah until Crowley shows and takes the grace of the angel and gives it to Cass. But Sam manages to trap Dean with holy water and handcuffs carved with devils-trap symbols.Īfter giving Crowley the First Blade, Sam takes Dean back to the Men of Letters bunker to cure him. While Dean and Cole meet and duke it out, Dean overpowers Cole and nearly kills him. After Sam learns that Dean is a demon, because of Crowley and the Mark of Cain, Sam eventually finds him, with help from Crowley, but so does Cole. But with his grace failing and rogue angels still on the loose, Cass faces the ticking clock of his own mortality. Meanwhile, Castiel, with the aid of Hannah, has to pick up the pieces in the aftermath of Metatron's campaign. Along the way, Sam encounters a former US marine named Cole Trenton, who apparently knows Dean and wants revenge for Dean killing his father. The road to recovering the wayward Dean takes Sam down dark paths, with consequences that will shake the boys to their core. The season begins with Sam's frantic search for his missing brother, who is gone without a trace.