The Men of Letters ask Mary to perform a special mission for them, which involves her recruiting Sam, Dean, and Castiel without their knowledge of who she now works for. The mission soon goes south and Castiel is mortally wounded.moreless
Sam and Dean must find a way to escape the black site where the government has imprisoned them. Meanwhile, Castiel and Samantha find themselves at loose ends with no idea where the brothers are or if they're even alive.moreless
Sam and Dean try to trap Lucifer, but discover that he's found a near-perfect hiding place: the President of the United States.
Lucifer plans to use his host body, Vince Vincente, to gather an army of fans and bend them to his will. Sam, Dean, Castiel, and Crowley try to track him down and stop him before it's too late.moreless
The sounds of a crying baby lure victims into an abandoned house, and Mary suggests that they investigate the case. Meanwhile, Crowley and Castiel team up to track down Lucifer, who is forcing Rowena to help him preserve his host body.moreless
Lucifer takes over the body of a rock star. Meanwhile, Dean, Castiel and Mary try to rescue Sam, but Dean is uncomfortable with putting Mary in danger, even though she insists on going along.moreless
Dean is reunited with Mary and Castiel, and they search for the missing Sam... unaware that the Men of Letters are torturing him for information on the American Hunters. Meanwhile, Crowley searches for Lucifer, who is leaving a trail of burned-out bodies in his wake as he jumps from person to person.moreless
With the fate of the universe in their hands, Sam, Dean, Castiel, Crowley, and Rowena come up with a desperate plan to kill Amara. However, one of them must sacrifice their existence to do so.moreless
The Winchesters ally with Chuck and Lucifer to destroy Amara, but discover that they need an even greater force to weaken her enough so that Chuck can strike the final blow.
While the Castiel-possessing Lucifer tries to take control of Heaven, Sam and Dean hear out Crowley on his plan to stop Amara.
Sam and Dean decide to take a break and check out a wrestling tour. However, when a wrestler turns up dead, the brothers suspect demonic influence. Meanwhile, Crowley escapes from Hell with a little help from a friend and seeks out a weapon to kill Lucifer.moreless
Sam locates an artifact capable of destroying Amara... that was lost at sea in 1943. The brothers convince Castiel--secretly Lucifer--to transport Dean back in time to recover the artifact.
While Lucifer tries to convince Sam to let him out of the cage, Dean and Crowley come up with a plan to seal the Devil away permanently. Meanwhile, Castiel joins forces with another angel to confirm if Amara is dead or not.moreless
While Dean tries to find Amara, Sam and Crowley convince Rowena to help them summon Lucifer from the cage so that Sam can try and persuade the Prince of Darkness to help them seal the Darkness away once more.moreless
While Castiel gets a lead on Metatron and interrogates him about the Darkness, Sam and Dean find Amara's location and try to sneak past Crowley's demons to get at the girl and kill her.moreless
While Crowley tries to bend Amara to his will, Sam and Dean track down Rowena so that she can undo the attack dog spell that she cast on Castiel... before it kills him.moreless
While Dean delivers Jenna and Amara to Jenna's grandmother, Sam tries to find a cure to the Rabid plague in Superior. Meanwhile, Hannah rescues Castiel from the other angels, and Crowley learns of the Darkness child.moreless
After the Darkness passes them by, Dean begins to remember his encounter with the intelligence at the heart of their new foe. Meanwhile, the Darkness spreads, turning men into killers. Crowley escapes Castiel and makes plans to return to Hell, while Castiel beseeches his fellow angels to help him.moreless
Sam has Castiel convince Crowley to find the three ingredients for the spell necessary to cure Dean of the Mark. Meanwhile, Dean continues to sink deeper under the Mark's influence, and contacts a former ally for help.moreless
While Dean hunts down Charlie's killers, Sam has no choice but to fulfill his end of his bargain with Rowena.
Sam and Dean investigate a woman whose eyes were removed and run into the mysterious Styne family again. Meanwhile, Sam goes behind Dean's back to recruit Charlie and Castiel to help Rowena decipher the Book of the Damned. In Hell, Crowley talks to Olivette and finds a bargaining chip that he can use against his mother.moreless
While Sam and Castiel free Metatron from Hell, Dean goes out drinking and meets Rowena. Meanwhile, Crowley decides what to about his mother.
The Winchesters investigate a series of deaths involving disembowelment. In each case, the victims attended the same church and confessed to the same priest. Meanwhile, Crowley captures Olivette and turns her over to Rowena in the hopes that she'll stop taking out her frustrations on his royal court.moreless
While Crowley tries to deal with his mother, Sam and Dean confront Cain over the Mark.
Sam and Castiel turn to Metatron for help trying to cure Dean, while Claire plans revenge against the man who killed her second father. Meanwhile, Rowena continues her plan against her son Crowley.moreless
Castiel turns to Sam and Dean for help, when he tries to help the daughter of the man he's possessing but she escapes. Meanwhile, Crowley and Rowena have a chat, and Dean worries about what will happen if he gives in to the Mark again.moreless
Sam and Dean track down a demon prostitution ring which leads them to the witch Rowena. They go after her, unaware that Cole is still on Dean's trail. Meanwhile, the husband of Hannah's host body comes looking for his wife, complicating things for Hannah and Castiel.moreless
Sam tries to cure Dean and remove his demonic essence, but discovers that his brother doesn't want to be cured. Meanwhile, Crowley realizes that he will need someone to rally the forces of Hell behind to maintain their loyalty, and seeks out a dying Castiel.moreless
Crowley discovers that Dean is becoming increasingly difficult to control, and contacts Sam to make a deal. Meanwhile, Sam escapes from Cole and returns to his hunt for his brother, and Hannah tries to make a deal with Metatron to save Castiel's life.moreless
Dean embraces his new life as a demon and hits the bars with Crowley. Meanwhile, Sam tries to track down his brother, unwilling to accept what Dean has become, and runs afoul of a man trying to get revenge on Dean for a past crime.moreless