Plot

Abaddon makes a deal with Crowley to stop the Winchesters and recover the first blade. Castiel tries to bring Gadreel to his side in the war against Metatron.

Abaddon travels to Leith, Scotland, in the year 1723. She barges into a house of a now confused guy. He tells her to leave, after which she tells him that he knows what he was about to do, she get's ready to do something but get's interrupted by another guy who walks into the house. She kills him, which scares the other guy. She then chants the time travel spell, which ends the scene.

Back to the present day- A guy walks up to a group of people, sitting at a table at a bar. He tries to get their attention but they ignore him, upon mentioning being chosen by Metatron they get interested in what he has to say, but it also catches the attention of some people, presumably angels, who were standing at the bar behind him.

The guy exits the bar and is walking through a back alley when a man stops to look in his direction. He stops walking, the man walks off but he get's ambushed. He is being held in a detainment room and gets scolded by a guy in a burgundy suit, telling him to watch what he says.

Sam and Dean arrive at the building where the guy is being kept and they find themselves at a high tech research facility, focusing on finding Metatron, lead by none other than Castiel. They boys meet up with him and exchange hugs.

-Cleveland Ohio- Crowley is having a meeting with his advisers, but when he asks who is on his side he quickly learns that he got betrayed by them as he hears Abaddon greeting him. Abaddon tells Crowley that he knows about the intervention with the Winchesters and tries to make a deal with him, join him so they can get rid of the Winchesters and deal with each other afterwards. Crowley refuses and says he will never join her, but Abaddon had a plan. She brings out the guy from 1723, Gavin, who ends up being none other than Crowley's son. Crowley is unfazed and tells her that they dislike each other. Abaddon then tells him that she knows all about his addiction to human blood and that there is at least some humanity left in him. Crowley says there is not a chance. Abaddon smirks and makes Gavin bleed out of his eyes, she makes it worse as time passes until Crowley gives in.

At the detainment room, the brothers try to get the guy to speak but he keeps his mouth shut. Sam tells Dean that he thinks the guy might have said that he was chosen by Metatron to sound cool, and that he doesn't really believe it, Dean agrees and the two start slagging the guy off . The guy gives in and suggests the fact he might be a decoy. Sam starts laughing and the continue slagging the guy off, subsequently making him speak and spill the beans.

-Cleveland Ohio- Gavin doesn't believe that Crowley is his father because he looks nothing like him and because he buried him himself. Crowley states that a lot can change in 291 years which confuses Gavin. He shows him a lamp which impresses him and Abaddon shows him the city night view which overwhelms him even more.

-Back to the Winchesters The boys continue poking fun at the guy and subsequently getting answers from him.

Gavin and Crowley catch up. Gavin is disappointed at his dad for reason he sold his soul. Crowley briefly explains that he became a demon himself, but Gavin snaps back saying he can't be talking with a demon. Crowley then tells him he is the king of Hell himself.

A girl walks into the detainment room at the facility to check on the guy but finds him dead. The guys don't know who did it and Castiel says it was an Angel kill. Dean says that the operation might be hacked and there could be a spy among the angels, he suggests that everyone could be lying about who they truly want to follow. Dean says it's time to see what's going on and leaves the room but Castiel wants to ask Sam about Gadreel.

Gavin and Crowley talk about Gavin's childhood and why he hates his dad, he mentions the fact that he can't read to which Crowley replies that it is underrated and that most of Europe couldn't read. Crowley taps Gavin's forehead and gives him the newspaper and tells him to read it which Gavin does, to his shock. Crowley says that being the king of Hell has its perks and Gavin starts feeling acceptation for it. He asks Crowley if him being the king of Hell makes him the prince and if that means that he will keep him from internally burning in Hell. Crowley sees that he is negotiating with him which makes him proud and Gavin acknowledges that it all might work out. Gavin wants to go back to his own time so he can board his ship to the new world, but Crowley knows what happened to it so he is not eager to send him back.

Meanwhile Castiel meets up with Gadreel and tries to talk him out of trusting Metatron. He tries to make a deal with him, but get's ambushed, Gadreel alerts him just in time.

Dean starts seeing flashbacks about the mark and zones out. The phone rings and Sam claps to get him back in focus. On the phone is Crowley, who is telling them that he found Abaddon. The boys drive to where Crowley stashed the blade. It's in a corpse. All of a sudden Sam hears violent snarling, Dean discovers it's a Hellhound and they make a run for it. Dean calls Crowley, who commands the Hellhound to stand down. They go back to the corpse and Sam fishes the blade out of the corpse's guts. Back in the Car, Dean calls Crowley to tell him they got the blade. Crowley tells him the location and uses one of the code words he learned when he tried to get Sam back when he was possessed by Gadreel. Abaddon doesn't fully trust Crowley as he has been plotting with the brothers for quite a while, so she shoots him in his shoulder.

Meanwhile, Gadreel tries to explain to Castiel that he did not know about the assassins. Castiel wonders why he is telling him and Gadreel tells him that there should always be honour, even in war. Castiel says that it proves a point about Metatron, as they met in good faith but Metatron used Gadreel to get to him. Castiel makes a deal with him and they part ways.

The brothers arrive at the location but Dean tells Sam to check the basement. Sam is puzzled. Dean arrives at the apartment and Crowley says he'll bring him to Abaddon. But Dean get's ambushed by a demon and then get's thrown at the wall by Abaddon. Meanwhile, Sam is checking the basement but finds nothing, he realises he's been had. Abaddon tells Dean what she is planning to do and mentions killing Crowley's son, which catches Crowley's attention. Dean fights Abaddon's grip, with the power of the blade. Abaddon throws him back and he drops the blade. He uses the power from the mark to grab it back and fights Abaddon's grip once again. Sam barges into the room, just in time to see his brother stabbing Abaddon. He doesn't stop, Sam tries to tell him to stop as he continually stabs her while she lies motionless on the ground.

After the fight, Crowley complains that they didn't help him with the bullet that Abaddon shot into his shoulder. Sam says that not killing him was enough. Crowley says that they owe him because he warned them that it was a trap. But Sam doesn't recall his warning because Dean didn't mention him saying the code word when they were on the phone with him. They exchange looks without saying a word and Crowley senses drama. Dean says he can't get over the fact that Crowley has a son. Dean reminds Crowley that Gavin has to go back to his own time, but Crowley says that his destiny is boarding a ship that sinks and that he want's to give his son a second chance of life. Sam says that changing the past will affect the past, but Crowley says that the two bend the rules all the time and that one guy doesn't impact anything. Sam says to Crowley that he doesn't get to bend the rules and Crowley asks if he can say goodbye to Gavin, who was in the room behind them. He goes to the room and slams the doors shut. The boys try to open the doors and once they succeed, Crowley and his son were nowhere to be found.

Crowley teleported himself and Gavin to a meadow and tells him about the boat he was about to board. Crowley says that his life can be better in the 21st century, but Gavin says he doesn't know anything about it. Crowley assures him that he will be fine. They exchange their farewell speeches and Crowley gives his son some advice before disappearing.

Sam and Dean are in the car and Dean says that he didn't tell Sam about the warning because he supposedly knew what Sam was going to do, mentioning standing alongside him as they enter that room. Sam get's a bit upset and says that that is exactly what they are supposed to do because they are partners. Dean explains that him touching the blade made him feel things he never felt before and that he knew that he had to go in alone. Sam thinks that the blade is doing something else to him but he doesn't know what, so he suggests keeping the blade far away from him. But Dean says no.