As the brothers deal with the aftermath of the opening of the Devil's Gate, Bobby Singer arrives to lend a hand. Sam desperately tries to find a way to save Dean from the ramifications of the pact he made to save Sam's life.
Dean reunites with an old flame that leads him to ponder what-ifs. Ruby reveals herself to Sam and sends him on a quest to find his mother's friends.
Gordon Walker plots to have Sam killed. Sam and Dean investigate a break-in at one of their father's warehouses, leading them to cross paths with a bounty hunter called Bela.
A case leads Sam and Dean to a small town that has been turned into a haven for addicts of all kinds. A confrontation leads Dean to form an unexpected connection with a demon. Sam's behavior strikes fear in Dean's heart that Azazel's warning might be coming true.
When fairy tales start coming to life, it's up to Sam and Dean to save Red Riding Hood from her kidnapper. Sam uses the Colt to try and break Dean's deal with the Crossroad demon.
When the sighting of a ghost ship appears to herald death for anyone who sees it, Sam and Dean's investigation causes them to run across Bela and discover a disturbing secret about her.
With Gordon on the hunt for Sam, the brothers' investigation into vampiric cases ends on an unexpected note that causes them to make difficult decisions.
With Dean's last Christmas upon them, the brothers disagree over whether they should celebrate, which causes them to reflect on old holidays as they investigate an evil Santa who has been dragging people into chimneys.
Ruby offers her help as the brothers deal with a case that involves witch-craft and a figure from Ruby's past. Dean discovers what fate awaits him upon his death.
When Bobby falls into a mysterious coma, the Winchester brothers race to uncover the details of the case he was working on and how to save him. Bela double-crosses the brothers and leaves with a precious possession.
When tragedy strikes when the brothers are on a case, Sam finds himself trapped in a loop that forces him to face his darkest nightmare: Dean's death.
When Bela tricks the Winchesters and gets them arrested, they find themselves trapped inside a police station with an army of demonic-possessed people coming for them, all under the guidance of Lilith, the new leader of Hell who wants to kill Sam.
When a crew of supernatural enthusiasts gets trapped inside a haunted house, they encounter the Winchesters who are looking into the case.
The Winchesters investigate a case where people meet gruesome ends after phone calls from late loved ones. Dean confronts the inevitability of his fate after he falls victim to the demon behind the calls.
As Sam pursues a way to save Dean, Dean goes after Bela and learns the identity of the demon who holds his contract. Bela reveals a way for Dean to get out of his contract.
With Dean's imminent death hanging upon them, the brothers and Bobby make one last try to find and kill Lilith in order to save Dean's soul from Hell.