Dean falls increasingly under the spell of the First Blade. Meanwhile, Metatron makes his move against humanity, as Sam, Castiel, and Gadreel try to stop him.
Castiel calls on the Winchesters to help when his army of angel followers are attacked, and Dean is all too eager to help under the First Blade's influence.
While Sam and Dean help Castiel interrogate one of Metatron's angels, Abaddon takes extreme measures to force Crowley to help her against the Winchesters.
Metatron tries to get Castiel to join forces with him. Meanwhile, Sam and Dean capture Gadreel.
Sam goes to check out a report of peaceful people transforming into violent killers and discovers a connection to a case involving his grandfather. Meanwhile, Dean deals with the aftermaths of acquiring the Mark of Cain and Crowley is eager to take advantage of his weakness.moreless
Crowley and a reluctant Dean go on a road trip to find The First Blade, the only weapon that kill their mutual enemy, Abaddon. Meanwhile, Castiel proposes to use Gadreel's remaining grace in Sam to track the angel, but warns that it could cause Sam permanent damage.moreless
In the wake of Kevin's death, Castiel proposes a plan to Dean to help Sam retake control of his body from Gadreel. However, they have to turn to Crowley for help.
Sam and Dean investigate an angel slaughter and discover that Castiel is already looking into the matter. The individual responsible captures Castiel, while Dean wonders whether ti's time to tell Sam the truth about Ezekiel.moreless
When Castiel calls the Winchesters about mysterious disappearances in his neighborhood, Dean is forced to keep Sam (and Ezekiel) away from Castiel by asking to help Kevin and Crowley decipher the tablet. Meanwhile, Crowley asks for one phone call to Hell in return for his cooperation.moreless
Ezekiel warns the Winchesters that a group of disgruntled former angels are hunting their friend Castiel, and the brothers set out to find him before it's too late. Meanwhile, Castiel learns more about the human lifestyle.moreless
Dean is devastated by the fact that the doctor tells him Sam won't make it, so he promises any angel willing to help that he will owe them a favor. Many angry angels want to find Dean and kill him, but Ezekiel gets to him first. At the same time, Sam is fighting for his life, and Castiel has a hard time surviving without his powers.moreless
Using the tablet half in his possession, Crowley prepares to make his final move in the grand game against Heaven. Only Dean, Sam, and Kevin can stop him. Meanwhile, Castiel and Metatron join forces and try to stop Naomi's scheme.moreless
Sam, Dean and Castiel are reunited and search the files of the Men of the Letters to find a film that could help them figure out the third trial. Meanwhile, Metatron asks for Castiel's advice about the problems in Heaven, and Crowley delves into the brothers' past... and some familiar facesmoreless
Sam and Dean receive a video message from Kevin which leads them to a casino in Colorado, where they find a mysterious recluse that might help them fill in the gaps in Kevin's research. At the same time, Crowley is winning at the tables. Meanwhile, Castiel tries to escape from Naomi and the other angels that are after him.moreless
Castiel returns and asks Sam and Dean to help him against demons seeking Lucifer's Crypt. When they set out to take on the demons, they rescue Meg, who is being interrogated for information. While Dean and Castiel go to find the Crypt, Sam and Meg fight a rearguard action to hold Crowley off.moreless
Naomi informs Castiel that Crowley holds an angel captive and he must save him so that Crowley doesn't learn their secrets. Castiel asks for Dean's help. Sam meets with Amelia, who asks him to chose whether to stay with her or never contact her again.moreless
Sam and Dean take on a case with Castiel, who has decided to become a hunter. However, they discover that the murder is only the latest in a string of cartoon deaths.
Sam and Dean are surprised to discover that Castiel has escaped from Purgatory, but doesn't remember how. Meanwhile, Kevin and his mother turn to a witch for help against Crowley but she betrays them to the King of Hell.moreless
Dean goes to help Benny, who has run afoul of vampires guarding his Maker. Left alone, Sam thinks about his year of retirement, but is soon called back in when Dean calls him for help.moreless
Crowley takes Kevin's mother hostage in an attempt to recover Kevin as he searches for the tablet. The Winchesters help Kevin rescue her, only to discover that she insists on joining them on their quest.moreless
The Winchesters and their allies, including Bobby, Castiel, Meg, and the Prophet Kevin, must try and stop Dick Roman and his Leviathans in a final showdown.
Meg summons Sam and Dean when Castiel wakes up. However, the brothers have other problems on their hands when they get word of a teenager who has been struck by lightning and become a prophet, and may hold the key to defeating the Leviathans.moreless
When Lucifer pays Sam another visit, he drives him to the brink, forcing Sam to enter a mental hospital. Fearing for his brother's life, Dean takes matters into his own hands, calling upon every hunter he knows. He receives the name of a healer from one hunter, only to find a familiar face waiting for him.moreless
Bridget runs into Dylan, a man who played an important role in the sisters' past. After discovering that Henry has one of Bridget's possessions, Malcolm befriends Henry so he can keep an eye on him. Catherine asks Andrew to make a big decision about Juliet that could dramatically change the dynamic of their family.moreless
Joel recaps the pop culture moments of the week.
The Leviathan possession of Castiel has devastating consequences which leads Sam, Dean, and Bobby back to Sioux Falls, Meanwhile, Sam puts himself and Dean in danger as he begins to crack under intense pressure from Lucifer's mind games.moreless
Castiel spares Bobby and the Winchesters and goes on his way to set right the wrongs of the world. However, when the brothers try to bind Death and use him to stop the new God, they discover that their former ally is one step ahead of them.moreless