Sam and Dean have spent their lives battling every kind of supernatural threat. Over the years, after countless bloody adventures, they’ve discovered that every victory comes with a price. The all-powerful Mark of Cain has threatened to consume Dean, turning him into one of the monsters he has spent his life hunting. Sam, with the help of Castiel, Crowley, and some unlikely allies, wages a desperate battle to save Dean from the Mark of Cain. Will Sam be able to find a cure in time to save Dean? And a more frightening prospect- does Dean want to be saved?