While Dean brings Mary up to speed on what has happened in the 30 years since she's died, 'Sam faces torture at the hands of the Men of Letters Meanwhile, Crowley tries to track down a weakened Lucifer, who is hopping from body to body.
Dean and Castiel continue their efforts to find Sam, and Mary insists on accompanying them. Meanwhile, Crowley recruits Rowena in his attempts to send Lucifer back to the cage.
An increasingly nervous Mary suggests to her sons that they investigate two mysterious deaths where the victims were attracted by the call of a baby. Meanwhile, Lucifer forces Rowena to help him preserve Vince's body, while Castiel and Crowley join forces to track him down.
When a priest reports that demons flayed a woman in his church, Sam and Dean investigate and find a religious family at the heart of the problem.
The Winchesters stumble upon a Thule plan to steal a pocket watch and abduct a young woman... and discover that Hitler is planning on making a comeback.
Sam and Dean go with Jody to the wake of a legendary Hunter, and discover that there are a few legends about themselves. They also find a killer among them when one of the Hunters turns up dead.
Lucifer in Vince Vincente's body stages a reunion tour of Vince's old band Ladyheart. When the Winchesters, Castiel, and Crowley learn of his plan, they head to LA to stop him.
Lucifer takes a new host body: the President of the United States. The Winchesters are forced to turn to the British Men of Letters for help to remove Lucifer's essence from his new host, but the Secret Service has other ideas.
After weeks of imprisonment, Sam and Dean figure out a way to escape the black site prison where they're locked up. Meanwhile, Castiel and Samantha try to get along without them.
When Castiel's former angelic squadmates turn up dead, he goes to investigate and the Winchesters insist on tagging along. They soon discover that the killer has a grudge against angels... and one in particular.
Sam is forced to call in Rowena when a witch hits Dean with a spell that causes him to lose his memory... and if the spell continues, Dean will soon die when he forgets how to breathe.
Mary convinces a Hunter, Wally, to call in Sam, Dean, and Castiel to deal with a demon. However, she soon discovers that the intel the Men of Letters gave her is bad... and they face a new, powerful threat.
When three teachers are brutally killed, Sam and Dean discover that they were all tied to a salvaged ship that Crowley's son Gavin was going to take to America until Crowley teleported him through time.
Mary brings Sam to a Men of Letters compound to convince him to join their cause. Meanwhile, Fetch approaches Dean and takes a different approach to recruitment.
Two campers are attacked by a hellhound, and Crowley reveals to the Winchesters that the creature is the First Hellhound. Meanwhile, Lucifer negotiates his release from Crowley's imprisonment, and an angel approaches Castiel with an offer.
Mick convinces Sam and Dean to take him on a case involving a werewolf attack. However, they soon discover that the British Man of Letters has an ulterior motive.
Sam and Dean get a lead on Kelly, but Dagon takes steps to prevent her from making contact with the Winchesters. Meanwhile, Lucifer tries to find a way to deactivate Crowley's wards on his host body, and Castiel is MIA.
The Men of Letters send Sam and Dean to investigate the case of a murderous goat man in Wisconsin while they check out the bunker to learn all of the Winchesters' secrets.
Castiel fails to kill Kelly yet again, and she tries to convince him that the baby should be born after all. Meanwhile, Sam and Dean discover that Castiel has betrayed them.
Sam and Dean get a call on one of Mary's phones from Alicia Banes. Alicia and Max are looking for their mother Tasha, and the trail leads to a boarding house in Wyoming. Meanwhile, Mary discovers that Ketch has been lying to her.
When Eileen turns up dead, torn apart by a hellhound, Sam and Dean realize that someone is killing the American Hunters. Meanwhile, Mary asks Ketch for a favor.
Sam and Dean try to escape the bunker after Ketch turns it into a deathtrap. Meanwhile, the brainwashed Mary goes after Jody and Alex, and Hess puts Phase Two of the Brit's plan into action.
As Kelly prepares to give birth to Lucifer's son Jack, the Winchesters team up with two unexpected allies to stop Lucifer.
