After the massacre at the ranch, Dean (Jensen Ackles), Sam (Jared Padalecki) and Castiel (Misha Collins) double their efforts to find a cure for the Mark of Cain but there is nothing in the lore that can help them. Desperate, Castiel comes up with an idea that Sam deems the "single worst idea I've ever heard." Meanwhile, Rowena (guest star Ruth Connell) continues to plot against Crowley (Mark Sheppard), and Castiel tries to mend his relationship with Claire (guest star Kathryn Love Newton) who is plotting revenge against Dean for killing her friend.
Elenco: Jensen Ackles , Jared Padalecki , Misha Collins , Alexander Calvert , Mark Pellegrino , Mark Sheppard , Alona Tal , Candice Accola , Felicia Day , Genevieve Padalecki , Jeffrey Dean Morgan , Julie McNiven , Katie Cassidy , Lauren Cohan , Osric Chau , Richard Speight Jr. , Rob Benedict , Samantha Ferris , Ty Olsson .