Castiel is reunited with Jack and, together with Sam and Dean, they head to a sleepy old western town to investigate a murder. Dean gets to live out his boyhood fantasy when he comes face to face with a famous, gun-slinging outlaw.
Sam and Dean continue to collect the pieces necessary to open a rift to the other world in order to save their family. Their latest quest leads them to a Men of Letters bunker from the 1920s and a hungry god from another dimension. Meanwhile, Ketch makes a shocking decision about Gabriel after an unruly encounter with Asmodeus.
Sam, Dean, Castiel and Gabriel must work together if they have any hope of bringing Mary and Jack home. Meanwhile, Rowena's encounter with Lucifer may alter the outcome of the journey for one of the heroes.