In Dearborn, Michigan, Matthew Hammond runs down the street as a car pursues him. It manages to disappear and get ahead of him. Hammond finally runs into his tenth-story apartment, only to discover that the car is waiting for him and runs him over.
The brothers arrive in Dearborn to investigate Hammond’s and Dean admits that it’s strange to be working a normal case after what they’ve been through recently. He notes that Sam seems good and Sam thanks him for letting Amy go. Inside, the detective in charge informs them that Hammond was apparently run over by a car. The brothers investigate the crime scene and find EM readings, and Sam locates red dirt. He also finds an AA chip and a monthly $50 charge to a place called Jane’s. Sam suggests that Dean check out the AA center but Dean refuses and goes to check out Jane’s instead.
Sam talks to the AA councilor and learns that Hammond recently panicked and considered suicide until she talked him down. Meanwhile, Dean talks to the clerk at Jane’s, a flower shop. She confirms that Hammond sent monthly flower deliveries to an Elizabeth Duren and gives Dean the delivery address. It’s a cemetery, and Elizabeth is a 10-year-old girl who died 10 years ago. The brothers return to their hotel and confirmed that she was killed when her neighbor, Hammond, accidentally ran her over. Dean, drinking, isn’t particular sympathetic. Sam convinces his brother to go out and burn and salt Elizabeth’s bones.
Christopher Fisher runs down the street with a dog in pursuit. He runs into a diner and locks himself in the bathroom, and then calls 911. As he says that there’s a dog after him, the dog appears behind him, jumps, and rips out his throat.
Dean and Sam return to their hotel room the next morning and Sam sees a newspaper article about Fisher’s death. No one saw the dog responsible and the 911 operator didn’t hear anything. Fisher was arrested five years ago for running a dog-fighting operation. Sam checks Fisher’s background and confirms that he made up for his crime by working at an animal shelter even after the end of his sentence, raising money for the shelter. Sam wants to head out to check Fisher’s body, and a tired Dean reluctantly agrees.
At the coroner’s office, Sam finds red dirt on the corpse. They confirm that the two victims walked near an abandoned apple farm. As they drive out, an older man named Warren runs out onto the road in front of them. Dean stops just in time and the man stands there, gasping for breath. The brothers take him back to the hotel and Warren says that they can’t do anything for him because it’s impossible. They promise they’ll believe him and Warren explains that he was put on trial and sentenced to death for killing a liquor store owner and his wife in 1981. He just got out of prison after thirty years, was drinking at a bar, Neal’s Tavern, and suddenly found himself in a courtroom inside of a red barn. Sam realizes that Hammond was at Neal’s Tavern just before he died. There were strange symbols on the wall and Warren draws them for Sam. Dean takes his brother outside and explains that he’s not interested in helping people who deserve what they got. Sam insists it’s not on them to judge but Dean doesn’t want to ignore what Warren and the others did. He admits that if the people he’s killed come after him as ghosts, they have a case. Sam insists on checking out the barn and Dean goes to Neal’s Tavern. His brother wonders if he’s going there to work or drink, and Dean says he hasn’t decided.
Sam asks Warren for his help but the man refuses, saying that the people he killed are waiting for him. When it becomes clear that Warren is staying put, Sam sets up a circle of salt to protect him, turns on the TV, and leaves to find the barn. As he goes, he calls Bobby and has him look up the symbols.
At Neal’s Tavern, Dean is drinking and a bald man bumps into him and keeps on going. Dean orders a double from the waitress, Mia, and starts flirting with her. She convinces him to talk about why he’s drinking and Dean explains that he’s guilty about doing something behind someone’s back. Mia points out that it doesn’t make sense to feel guilty if he had to do it. The bald man listens closely from down the bar, while Mia invites Dean to join her in an hour when she gets off the end of her shift.
Sam finds the red barn at the apple farm and locates red dirt on the floor. As he looks around, Bobby calls and tells him that the symbols are Egyptian and refer to Osiris, the God of Judgment. The lore says that he can see into the human heart, find guilt, and eliminate anyone who has it. Osiris pops up from time to time, executes the guilty, and disappears. Bobby tells Sam to get out of town with Dean because Osiris homes in on the guilty.
Dean waits outside the bar for Mia. His phone rings but as he answers it, the bald man grabs him and teleports him away, while the phone drops to the ground.
Later, Mia comes out and finds Sam’s phone, and hears it ring. She answers it and tells Sam that she was supposed to meet Dean, and he drives in to meet her.
At the hotel, the lights flicker and the TV goes out. Warren runs out and the ghosts of the liquor store owner and his wife confront him. The owner draws a gun and kills Warren.
Mia shows Sam where she found Dean’s phone and he finds red dirt on the sidewalk. He then goes to the barn and discovers that there are now braziers and Egyptian statues. Dean is chained to a chair and the bald man, Osiris, is dressed in Egyptian judge’s robes. Osiris calls out to Sam to come in, and Sam briefs his brother on Osiris’ nature. Sam refuses to leave and insists that Dean should have a lawyer. Amused, Osiris agrees and starts to call witnesses. Sam objects but Osiris overrides him, saying that he only needs three witnesses.
For his first witness, Osiris calls Jo Harvelle to the stand. She explains that she and Dean worked together as hunters and that she trusted him. Osiris asks if it was hard for her to work Dean considering her feelings, and if Dean had anything to do with getting her started as a hunter. Jo insists that she had no feelings and Osiris asks if she would have chosen the same path if she hadn’t met Dean, a path that ended up with her dying in a hardware store. Sam cross-examines and has Jo explains that her father was a hunter and that she idolized him and became a hunter to be like her dad. Jo admits that she does and tries to explain to Dean, but Osiris sends her away.
Osiris gives the brothers a moment to confer and Sam asks Dean who else that Osiris will call. Dean says that he has no idea, and Osiris calls Sam to the stand. The god points out that Sam was happily out of the family racket until Dean showed up and called him back to life as a hunter. From there, people died and Sam was almost killed. Osiris asks if Dean dragged Sam along so he wouldn’t be alone, and Sam asserts that he would have been pulled in no matter what. The god agrees but explains that Dean will be the one who decides if he has to suffer or not. If Dean believes that he’s innocent, then Osiris will let him go. However, he explains that people want to be judged and feel real punishment.
Sam calls Dean to the stand and Osiris allows it. He carefully leads his brother and gets him to state that he has nothing to feel guilty about. Dean doesn’t appear convinced but plays along, and Sam rests his case. Osiris asks if Dean wants to hear from the last witness, and Dean realizes that he’ll call Amy. Rather than expose what he did to Sam, Dean tells him to get on with it. Osiris declares Dean guilty in his heart and sentences him to die, and suggests that he get his affairs in order.
The brothers return to the hotel and see the police bringing Warren’s body out. Sam and Bobby continue looking for a way to save Dean. Bobby finally discovers that stabbing Osiris with a ram’s horn will kill him for a few centuries. Sam figures that they can steal a ram’s horn from a synagogue and gets the keys from the Impala. Dean reminds him that Osiris will send Jo after him, and Sam tells him that he knows what to do. Dean makes a circle of salt just as Jo appears.
Sam breaks into the synagogue and finds the ram’s horn. A rabbi comes in and wonders what he’s doing.
Osiris goes to Neal’s Tavern and listens as another guilty woman tells her sins to Mia.
Jo insists that she wouldn’t kill Dean if she had a choice and says that Dean deserves better. He insists that she’s the one who deserves better. Jo says that her life was good but Dean says that she and Sam were both kids, and he didn’t stop to think that hunters are never kids. However, he wanted someone with him. Jo says that Osiris was right that Dean carries a lot of guilty around that he doesn’t deserve, but Dean wonders what would be left if he set that aside. Jo suddenly turns somber, says that it’s time, and goes to the stove to turn on the gas. Dean remembers her dying the same way, in a gas explosion.
Jo freezes the window, shattering it, and summons a wind to blow away the salt. She warns Dean that Osiris is making her do it and he says that it’s okay. Jo then takes a lighter out of Dean’s pocket.
The guilty woman leaves Neal’s Tavern and Osiris follows her to her car. As he prepares to teleport the woman away, Sam arrives with the ram’s horn and stabs him, reducing the Egyptian god to a withered corpse in a matter of seconds.
Jo smiles in relief, strokes Dean’s cheek, and then disappears.
Later, Dean and Sam head out of town and stop for a beer. Dean explains that Jo actually seemed happier, and asks why Sam defended him. Sam says that he didn’t have a choice and asks who the final witness was. Dean lies and says that it could be anyone dead that they know, and then asks why Osiris ignored Sam. Sam explains that he’s stopped feeling guilty after his time in Hell, when he paid the price for what he had done before. He’s ready to put the past aside and move on with his life, and right here and now he feels good.