Castiel issues a warning to Dean, Sam and Bobby; Dean winds up in a confrontation with Death; Sam struggles with the broken wall in his head.
Castiel struggles with the downside of his new power; Sam suffers from hallucinations; Bobby worries that Dean will collapse under the weight of his responsibilities.
Dean is angry when Sam disappears to pursue a case with clues identical to a mystery he encountered as a kid.
Sam and Dean discover Osiris, a vengeful Egyptian god, is responsible for a series of gruesome murders; Osiris puts Dean on trial.
Sam and Dean meet a witch whose anger over her husband's philandering has proved fatal for the townspeople.
When murderous clones of Sam and Dean are created, the Winchester brothers become wanted men; Sam and Dean turn to a quirky surveillance expert (Kevin R. McNally) for help.
Dean and Sam visit a town full of people claiming to be psychics after residents are gruesomely murdered.
While on a hunt, Sam encounters someone from his past; Dean teams up with a quirky hunter named Garth.
Dean, Sam and Bobby track a creature that has been attacking people in a New Jersey state park; Dean realizes a restaurant's special sandwich appears to be making people go crazy.
As Dean and Sam tackle a high-stakes mission, Bobby turns to an old friend for help solving a deeply personal case.
Dean becomes obsessed with finding out how to take down Dick Roman (James Patrick Stuart); Sam helps a teenager search for her father (Ian Tracey), a hunter who disappeared.
The God of Time sends Dean back to 1944 where he is arrested by Eliot Ness; Sam is surprised to see an old friend.
Dean and Sam investigate gruesome attacks in which victims are branded with a strange symbol; Dean meets a woman (Sara Canning) at the town bar.
When Sam and Dean head to Kansas to investigate a case at a pizza chain that hosts children's parties, Sam is forced to confront a childhood fear.
Sam and Dean return to a small town where a demon they exorcised four years ago has returned; a psych ward patient recounts his memories of being possessed.
When a ballerina dances herself to death, Sam and Dean learn that her shoes were cursed; Dean starts to succumb to the spell after he accidentally touches the shoes.
Driven to the breaking point by Lucifer, Sam ends up in a mental hospital; Dean's plea for help leads him to a healer with the face of an old friend.
A hunter surprises the brothers with a request for help; Sam and Dean battle a Japanese creature that can be seen only by drunken people.
Shortly after Annie Hawkins (Jamie Luner), an old friend and hunter, asks Sam and Dean for help with a case, she disappears.
Dick Roman (James Patrick Stuart) acquires a hard drive that contains sensitive information about Dean and Sam; Bobby tries to help the brothers retrieve the hard drive, but his anger toward Dick gets in the way.
Meg contacts Dean and Sam with news that Castiel is conscious and talking; a teenager becomes a reluctant prophet after being struck by lightning.
Dean and Sam need to find three items if they want to defeat Dick Roman (James Patrick Stuart) and the Leviathans; Bobby's new trick turns out to be very dangerous.