Sam tries to release Dean from the Mark of Cain. Meanwhile, Crowley seeks the help of an unlikely ally after encountering problems due to Dean's behavior.
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 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.
In Chicago, Sam and Dean encounter five clans of monsters that run the city's underground... and Ennis, a young would-be hunter who seeks revenge on one of the clans.
Sheriff Mills calls in Sam and Dean when a prisoner under her protection is abducted by vampires.
Metatron tries to get Castiel to join forces with him. Meanwhile, Sam and Dean capture Gadreel.
Clarke and Finn grow closer as they try to communicate with the Ark. Meanwhile, Bellamy maintains order within the group.
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 starts taking human blood again and Abaddon learns of his search for the First Blade. To find the Blade before the Knight of Hell does, Sam and Dean enlist the help of a former Man of Letters.moreless
Sam and Dean travel to Washington to investigate the death of a young girl, only to discover that Harry and Ed, the Ghostfacers, have arrived before them.
After receiving some shocking news Stephen attempts to restore order in both his worlds by striking a deal with Jedikiah.
Cara and Russell contend with a new break-out and must also deal with an ULTRA trap.
Meanwhile Jedikiah is closer to developing a secret technology that could change his future.
While Castiel falls into the hands of Bartholomew and his faction of angels, Sam and Dean make a startling discovery about the Men of Letters bunker... and a special captive that Abaddon's demons are holding.moreless
Stephen is upset with Jedikiah for going back on his word, forcing him to face The Founder.
In order to protect Astrid, Stephen must make a deal to bring in a powerful break-out and elsewhere John clashes with Cara which forces her to issue a harsh punishment.
Sam and Dean go undercover at a spa when murder victims turn up hundred of pounds lighter after their deaths. The brothers soon discover that something is feeding on the victims' fat.
Stephen feels uneasy about fellow ULTRA trainee, Hillary, who has her own secret agenda. After his mother insists the family go camping with Peter, Stephen asks John and Cara to ensure everything is okay with Astrid while he's gone.
Garth ends up in the hospital, and Sam and Dean go to find out what happened. However, when they arrive, Garth goes on the run and the Winchesters are surprised to discover what really happened.moreless
Stephen and his fellow ULTRA trainees are given a test by Jedikiah to determine their worthiness as Agents but not everyone is happy to work as a team.
Cara is faced with a visitor from her past and John works with a new breakout while Russell is sent on a dangerous recon mission that could force a clash between different groups of Tomorrow People
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.
When John finds himself in a dangerous situation Stephen finds he is unable to help without revealing his duplicity to ULTRA. Also not satisfied with the answer he discovered about his father's death Stephen decides to take drastic action to find the truth with help from his fellow Tomorrow People.
Cara and Russell negotiate a trade with Jedikiah which ultimately makes Jedikiah take a big risk.
Stephen is determined to uncover what he hopes is the key to finding his father, and crafts a plan with The Tomorrow People that involves getting inside Jedikiah’s head. Meanwhile, Cara and Russell encounter an uninvited visitor in the subway tunnel base.
Stephen takes a risky opportunity and snoops around ULTRA.
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 four members of the same church chastity group disappear, Sheriff Jody Mills calls in Sam and Dean for help. However, Dean soon disappears and Sam and Jody have to go after him.moreless
A man named Sonny calls Dean for help, and Sam is surprised to learn that Sonny and Dean spent time together at a home for delinquent boys. Sonny needs help dealing with a ghost and the Winchesters agree to help investigate. Meanwhile, Dean links up with an old girlfriend from his time in the home.moreless
After Stephen decides to have some fun with his newfound powers, Jedikiah takes extreme measures to ensure it doesn't happen again.
John feels tension between himself and Cara after he and Russell return from their trip while Stephen decides to try and handle a dangerous new breakout on his own but finds himself in over his head and needing help from his fellow Tomorrow People.
Stephen becomes even more determined to find out what happened to his father after having a moment of clarity about him.