Sam tells John and Dean the details of his vision of the young girl running through the town of Salvation. They drive to the town and John warns his sons that the yellow-eyed demon is more powerful than other demons, and only the Colt can stop him. He insists that his son only use the three remaining bullets against the demon.
As they approach Salvation, Dean suddenly breaks to a halt when he sees a young woman, Terry, lying on the road ahead. John gives Dean the Colt and tells his son to shoot if he has to, but warns him that the Colt will kill the possessed as well as the possessor. Once he makes Dean and Sam promise to shoot no matter who the yellow-eyed demon possesses, John approaches Terry and orders the demon possessing it to reveal where the demon is. The woman's eyes go black and she slams John against a tree. Other demons emerge from the woods as Dean orders the demon in Terry to stop. John tells his son to abandon him and leave rather than waste the bullets, and Sam throws Dean into the Impala and drives off. Once they make good their escape, the demon in Terry takes out a knife and stabs John in the stomach.
As it starts to rain, Sam pulls over and Dean angrily asks why he left their father behind. Sam reminds Dean what John made them promise, but Dean doesn't want to lose the only two people he has left. As they talk, Terry calls them on John's phone and begs them for help. She explains that John is hurt and the demon possessing her has left her body. She tells them that they're at the Sunset Building in Manhattan and then the demon repossesses her, forcing her to hang up.
The next day, the brothers drive to Manhattan and park near the Sunset Building, which is under construction. Using binoculars, they spot Terry walking on one of the upper levels, her eyes black, and realize that the demon is back in control. Dean figures that they have no choice but to go up even though it's a trap.
The possessed Terry waits for the elevator but when it opens, there's apparently no one inside. She goes in and Dean, hiding to the side, yanks her in and then hits the button for the first floor and jumps out with Sam. However, the demon pries the door open and Sam douses it with holy water, driving it back inside and allowing the elevator can descend.
The brothers continue into the building and find a vast central shaft, filled with catwalks. The wounded John is tied to a pillar in the very center and they cross the catwalk to cut him free. Sam douses John with holy water and confirms that he's demon-free, and John tells them that he let the Terry-demon capture him so that it would take him to the yellow-eyed demon's hideout and use him as bait to force Sam and Dean to bring the Colt.
Before they can leave, the Terry-demon returns and blasts them, knocking Sam off the catwalk. He lands on another one below and hangs on, but the demon prepares to cut him loose and let him fall to his death. Dean arrives and shoots it through the heart with one of the remaining three bullets. A grateful Terry looks up at him, freed from the demon, and then falls down the shaft. Dean pulls Sam up and asks him to hold onto the Colt. Sam tells him that he shouldn't feel guilty for killing an innocent woman, and Dean admits that he couldn't let Sam die no matter what the cost.
Bobby arrives in a helicopter and has the pilot hover outside while he calls over the loudspeaker, telling Sam and Dean that John called to ask him to watch over the brothers if anything happened to him. They realize that the demons have surrounded the building and Bobby tells them to meet him on the roof. As they help John up the stairs, Dean asks John if he's mad at him, and his father says that he appreciated what Dean did, since he and Sam get too obsessed and Dean is the one who looks after them.
The trio get to the roof and Bobby has the pilot bring the helicopter down. However, the young girl from Sam's vision steps out and telekinetically slams the helicopter down onto the roof. John says that it's the yellow-eyed demon and asks Sam for the Colt so he can finish it off. However, Dean tells his brother to stop, warning that the real John would have been furious at him for wasting a bullet to save Sam. He asks Sam for the Colt, reminding him that John said the yellow-eyed demon was far more powerful so it could resist the holy water test. John accuses Dean of being the yellow-eyed demon, but Sam considers and then tells "John" that he's been with Dean long enough to know that he's the real thing.
Giving up the charade, the yellow-eyed demon reminds Sam that if he shoots him he'll kill John as well. It then unleashes a wave of supernatural energy out from the tower, crippling Dean. As Dean falls to the roof, bleeding, Sam demands to know why it killed Mary and Jessica. The Demon informs him that it has a plan for Sam and the other children it has prepared, and boasts that Jessica was going to ask Sam to marry her just before it killed her.
The yellow-eyed demon dares Sam to shoot, killing it and John. Sam can't do it, but Dean crawls forward and grabs the Demon's ankle, apologizing to his father for failing to protect him and Sam. He tells John that he has to fight and collapse, and John manages to resist the demon's possession long enough to tell Sam to take the shot and kill him and the demon. As Bobby runs up, yelling not to shoot, Sam aims and fires... wounding John in the side. The demon bursts out of John and soars off into the clouds, and an angry John tells Sam that he should have shot to kill. Bobby goes to Dean while Sam tells John that he's changed since then and he couldn't kill his own father.
Later, Sam drives the Impala with John and the injured Dean, while Bobby follows them. Sam points out that they still have the Colt and one bullet, and all they have to do is track down the yellow-eyed demon. A young girl steps out onto the highway ahead of them, her eyes black, and telekinetically throws the Impala off the road.
Written by Gadfly on May 22, 2016