3.01 Magnificent Seven

In Oak Park, Illinois, Walter Rosen is putting out his garbage when the street lights flicker and dark clouds roil. From the sky a stream of black substance overtakes Walter. He opens his eyes and they are black - he has been possessed by a demon.

Meanwhile, Sam studies the legend of Faust in order to find a way to help undo the deal Dean made with the Crossroads Demon, as Dean has a sexual romp. Bobby calls with news on a cicada swarm and crop failure in Nebraska. it is the first possible sign of demon activity they've had. When the Devil's Gate in Wyoming opened, strange storm clouds appeared over seventeen cities, but there have been no reports of demonic activity so far.

The boys rendezvous with Bobby at a farmhouse where they find a family who have starved to death in front of a television, despite the kitchen being full of food.

While searching the house, Dean is jumped by Isaac, who along with his wife Tamara, are hunters. Back at Isaac and Tamara's house, they make it clear they don’t want to work with the Winchesters, as they blame them for all the demons that have been let loose when the Devil's Gate was opened.

Outside, in the shadows, a woman watches them.

Bobby and the boys investigate the death of a woman outside a shoe store. Examination of the security video shows Walter Rosen interacting with the woman responsible for the murder just before the crime. While at the crime scene, the woman who earlier had watched the house, follows Sam. Even though Sam senses that somebody is following him, she disappears into thin air before Sam can see her.

Using a photo of the man, Bobby, Sam and Dean trail him to a bar, where Bobby urges cautious surveillance. However, Tamara and Isaac arrive and enter the bar. They have also spotted the possessed Walter Rosen, but when Isaac prepares to use Holy Water to see if he is a demon, they are detected. As one by one the eyes of the bystanders turn black, they bar’s patrons are all revealed to be demons. Tamara and Isaac are restrained, and Tamara is forced to look on while a man hands Isaac a container of drain cleaner. He is overcome by some force, and drinks the poison.

As Walter collapses, a car bursts through the door, and Sam, Dean and Bobby fight the demons, rescuing Tamara, and throwing Walter into the trunk where he is held by a Devil's trap.

Back at Tamara’s house, Bobby has deduced that they are dealing with the Seven Deadly Sins - demons, as documented in Binsfeld's Classification of Demons in medieval times. They interrogate Envy who is possessing Walter. He taunts them that humans possess all the vices they represent, and warns that the other demons will track them down. He taunts Dean about his lust and gluttony, and Tamara about her wrath. Tamara then exorcises Envy, and Walter dies in the process.

Dean offers to battle the demons while the others escape, - a suicide mission - but Sam and Bobby agree they need to face the demons together. One of the demons possesses Issac’s corpse, and calls in agony to Tamara to help him, but she is aware of the ruse and stabs him with a stake of Palo Santo. However she has broken the salt line at the door, and the other demons rush in.

Bobby traps Sloth under a Devil's trap while Lust tracks down Dean and tries to seduce him, until he manages to push her into a tub of Holy Water. Sam is confronted by the others, led by Pride. He knows who Sam is, and his connection to the Yellow-Eyed Demon, calling Sam a prodigy, and the boy king. As Sam is attacked, the mysterious woman who had followed him earlier appears, who we will later know as Ruby, and attacks the demons with a knife, which kills two of them, while Sam helps her kill the third. The woman disappears after revealing she knows who Sam is. Dean confesses to Sam that part of the deal was that if he tried to get out of it Sam would die. Sam charges that Dean is selfish and is putting him through the same thing Dean felt after John gave his life for Dean. Dean says that he actually feels great for the first time in a long while, and that he wants to enjoy this last year by killing some evil and having fun.
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