After learning of the Three Trials to close the Gates of Hell from the Prophet Kevin Tran, Sam began the Trials, ultimately reaching the final Trial which was to cure a demon. After capturing the King of Hell Crowley, Sam began using Crowley for the ritual, but was ultimately stopped at the last minute by his brother Dean who had learned from the angel Naomi that if he finished the Trials, he would die. Dean managed to stop Sam from finishing the Trials, but he collapsed from them shortly afterwards.
While the Winchesters were trying to seal up Hell, the angel Castiel was approached by fellow angel and the Scribe of God, Metatron to perform the Angel Trials to close the Gates of Heaven and lock up the angels as well to force them to settle their differences. However, this turned out to be a trick to get the ingredients for a spell designed to make the angels fall to Earth in revenge for Metatron being forced to leave Heaven. Despite Naomi's warnings, Castiel got Metatron the needed ingredients and Metatron betrayed him. Metatron then took Castiel's grace, the last ingredient to the spell which rendered him human. Metatron sent Castiel down to Earth to live a human life before dying and coming to Heaven to tell Metatron his story. Shortly after Metatron sent Castiel back to Earth human, he cast his spell and all of the angels fell.
Desperate to save Sam after he loses consciousness, Dean takes him to Linwood Memorial Hospital in Randolph, New York for medical help where Sam enters a coma. After examining Sam's condition, the doctor tells Dean that Sam has massive internal burns affecting many of the internal organs. Also, oxygen to Sam's brain has been severely deprived, resulting in Sam's body putting him in a coma to try to protect itself from further harm. The doctor warns that if Sam's body continues down its path, the life-support machines may keep his body alive, but he will be brain-dead and that there's nothing more he can do for Sam. After the doctor tells him that Sam's fate is now in God's hands, Dean storms out of the room.
After leaving Sam's room, Dean goes to the hospital chapel where he desperately prays to Castiel for assistance, but Castiel doesn't answer. With no other option, Dean prays to any angel listening, telling them that he needs their help and his location. In exchange for the help of any angel willing to do so, Dean promises to help them in return when they need it which, despite them not seeing eye to eye they know he is good for.
Waiting for any sort of response, Dean is approached by a woman named Kim Schortz and asks if she's an angel. However, she is not and is instead a grief councilor come to talk about Sam's impending death. Dean refuses to give up and realizes he's got something better than an angel: he's got the King of Hell locked in his trunk. Dean goes to the Impala in the parking garage and asks Crowley to signal if he's still alive locked inside the trunk. Moments after Crowley answers yes, an angel grabs Dean from behind and holds an angel blade to his throat.
The angel pins Dean to the Impala's trunk and demands the location of Castiel, threatening to rip out Dean's throat if he doesn't comply. When Dean asks who's looking for Castiel, the angel tells him that every angel who got ejected from their home is looking, causing Dean to tell him that he has no idea. The angel goes to attack Dean with his angel blade, but is stopped by Gadreel who tells the other angel that Dean had prayed for their help and they are supposed to be creatures of compassion, not wrath and should help Dean. The other angel doesn't recognize Gadreel who promises to introduce himself if the angel disarms himself. The angel lets go of Dean and seems to be about to disarm, but instead hits Gadreel who asks if that's how he treats another angel injured in the Fall. The two angels fight with the enemy angel losing his angel blade. Due to Gadreel's injured and weakened state, the other angel easily beats him, eventually knocking him against a van, shattering its driver's side window. Before the two angels can continue their fight, Dean recovers, grabs the angel blade and stabs the enemy angel through the back with it, killing him. Dean then turns to Gadreel and asks who he is. Gadreel tells Dean that it doesn't matter who Gadreel is, but he knows who Dean is and has heard his prayer and come to help. Gadreel, injured by the Fall and his fight, then passes out.
After Gadreel passes out, Dean traps him in a circle of holy fire in order to keep him safely contained while he gets answers from him. When Gadreel wakes up, Dean asks for his name and Gadreel lies that it is Ezekiel, an angel who had died in the Fall. Dean questions how he can be sure that Gadreel is not hunting him or Castiel like the other angels and Gadreel tells him that there are many angels who he is sure are hunting for Castiel and are on their way there now. When Dean asks how he knows, Gadreel tells him that Dean putting out an open prayer like he did means he must be desperate. Gadreel assures Dean that some angels still believe in their mission which means they believe in both Castiel and Dean. Dean asks Gadreel about what the angel had mentioned about being injured in the Fall and Gadreel confirms it and that fighting the other angel made things worse, but he offers what strength he has left to help Dean. Dean believes Gadreel and releases him from the holy fire to help save Sam.
Dean takes Gadreel to Sam's room where Gadreel confirms that even after the Fall he should still have the power to heal, but Sam is very weak. Dean then receives a phone call from Castiel who tells him that Metatron tricked him and made the angels fall. Dean tells Castiel that Sam is dying and asks if Castiel has heard his prayers. Castiel tells Dean that Metatron took his grace and for Dean not to worry about him. Castiel asks what Dean is doing to save Sam and Dean tells him about "Ezekiel" trying to heal Sam. Castiel tells him that Ezekiel is a good soldier and will be able to help him until he can get there. However, Dean tells Castiel not to come as there are angels after him and the angels are pissed. Castiel tells Dean that some angels are simply lost and looking for direction and that he has met one who he wants to help. Dean warns Castiel against this as helping angels is what got him in trouble in the first place and tells Castiel until they can get everything sorted out, to trust no one. When Castiel still insists on helping, Dean reminds him that there's now a war on between the angels and its Castiel's fault so they will be searching for him. Dean points out that without his grace, Castiel is human and will now have to deal with all the human things that come with it. As Castiel tries to continue to argue, the hospital starts to rumble and Dean realizes that another angel is likely coming. Dean orders Castiel to get to the Men of Letters bunker alone and hangs up to deal with the new angel arrival.
Dean returns to Sam's room where he asks Gadreel if the rumbling is another angel. Gadreel confirms it, telling Dean that its an angel seeking a vessel and they need to move. Dean tells Gadreel that if they move Sam, he will die, but Gadreel warns that if they stay, they could all die so Dean puts up angel warding to buy them some time. The warding will keep any angels from entering or exiting the room and Gadreel assures Dean that he can still heal Sam even with the warding. Moments later, Gadreel senses the angels arrive and Dean tells him to save Sam and not let anyone in but him before heading out to confront the angels.
Dean heads out into the hospital where the angels' arrival causes all of the glass windows along the hallway to shatter. Dean pulls the fire alarm and starts getting people to evacuate rather than panic. As he helps Kim Schortz, the farmer angel arrives armed with an angel blade. Recognizing the man as an angel as a result of his angel blade, Dean draws the one he took from the angel he killed and tells Kim to stay behind him. However, the angel that was searching the hospital for a vessel found one in Kim and attacks Dean, disarming him and hoisting him by the throat. The two angels drag Dean to outside of Sam's room and Kim demands to know where Castiel is, threatening to make Sam wish he were dead if Dean refuses. Dean wishes the angels luck getting past his angel warding, but the farmer angel grabs a fire axe and uses it to start breaking down the door to Sam's hospital room on which some of the warding is located, breaking the warding on the door in the process. Kim continues to threaten that she will strip off all of Sam's skin and make Dean watch, but Dean continues to refuse to tell the angels what they want to know and taunts them, causing Kim to viciously attack him. Kim continues to attack Dean while the farmer angel smashes down the door of Sam's hospital room with his fire axe. Unable to beat the two angels in a fight, Dean distracts them by pretending to give in while in actuality using the blood from his injuries to draw an angel banishing sigil on the floor. Dean tells the angels that he'll tell them what they want to know if they answer one question. When Kim tells him to ask, Dean asks them "if Heaven is locked, then where do you go when I do this?" and exposes his angel banishing sigil. Before Kim or the farmer angel can react, Dean activates the angel banishing sigil and banishes the two angels, ending his fight with them.
Reentering Sam's hospital room, Dean finds Sam's heart monitor showing that Sam's body is now failing and that Gadreel failed to heal him. Gadreel explains that he's weaker than he thought and the angel warding isn't helping. Dean quickly starts crossing out the angel warding to help restore some of Gadreel's strength, but Gadreel tells him that if he could save Sam he would, but its too late as both he and Sam are too weak for him to heal Sam in time. Dean desperately asks if there's no way for Gadreel to save Sam and Gadreel tells him there's no good ways. Dean desperately asks for any way even if its a bad one and Gadreel suggests that there's a chance he could heal Sam from the inside. Dean realizes that Gadreel means possession and tells him "no way." Gadreel accepts this, telling Dean its his call, but Dean tells Gadreel that its Sam's call and Sam would rather die than be possessed by anything again. Understanding, Gadreel shuts off the monitor and prepares to leave Dean alone with Sam, but Dean stops him at the last moment. Dean asks for proof of how bad off Sam is to consider Gadreel's idea and Gadreel links Dean to Sam mentally, showing him that Sam is meeting with Death in his mind and discussing going with Death and Death making Sam's death final which Death promises that he can do. Dean realizes he has no choice and asks Gadreel how his plan will work. Gadreel explains that its one of mutual benefit: once inside Sam, Gadreel will heal Sam while healing himself. Dean points out that even if he agrees to the plan and says yes, Sam will never say yes to Gadreel which will prevent him from being able to possess Sam. Gadreel points out that Sam would say yes to Dean however.
Once again, Gadreel links Dean's mind to Sam's as Sam is about to go with Death. Dean appears in the cabin Sam is meeting with Death in in his mind and asks for a moment with Sam which Death grants him. Dean tells Sam he has a plan, but Sam tells him that its too late and he's going with Death, asking why Dean is even there, thinking he is a manifestation of his subconscious that wants to fight. Dean tells Death that its not Sam's time, but Death just tells him that its Sam's choice, not his. Dean reminds Sam that he made Sam a promise in the church that its the two of them "come whatever", but he can't help Sam if Sam doesn't let him in and help. Dean tells Sam "there ain't no me if there ain't no you." After a moment of uncertainty, Sam asks what he needs to do. Dean simply asks him if that's a yes and Sam tells him "yes." Having gotten what he needed, Gadreel takes over and uses Sam saying "yes" to Dean's plan, which was to have Gadreel possess him, to take Sam as his vessel.
With Gadreel now in control of Sam, he and Dean leave the hospital before any more angels can arrive, leaving behind Gadreel's confused vessel. As they leave the hospital, Dean asks Gadreel about Sam's condition and Gadreel informs him that its not good and there's a lot of work for him to do to heal Sam of the damage from the Trials. Gadreel confirms that Sam will wake up and won't feel Gadreel inside of him and tells Dean that Sam must not know of Gadreel's presence inside of him. Gadreel explains that if Sam knows of Gadreel's presence inside of him and doesn't accept it, he can eject Gadreel at any time, especially with Gadreel as weak as he is right now. Dean reluctantly agrees to keep the secret until Sam is strong enough to survive without Gadreel or he can find a way to tell him without freaking out. Dean and Gadreel decide to erase Sam's memory of his experience in the hospital so he won't get suspicious. That night, Sam wakes in the Impala with no memory of anything beyond passing out after the angels started falling. Dean tells Sam that he was asleep for a day and Dean just drove around with him as he knew Sam would pull through. Dean tells Sam he meant what he said at the church about Sam being capable of anything and that Sam proved him right. Believing himself to be fine, Sam decides that they need to get to work on putting the angels back in Heaven.
Following his possession of Sam, Gadreel emerges at times when his help is needed to protect Sam or due to the situation and to warn Dean about not letting Sam know about him. However, after Metatron offers Gadreel the chance to regain his honor by helping him rebuild Heaven under Metatron's rule, Gadreel murders Kevin Tran and takes full possession of Sam's body. With the help of Crowley, Sam learns of Gadreel's possession and expels him, causing Gadreel to return to his original vessel and resume his work for Metatron in that form. Sam is left furious with Dean's actions and it strains their relationship for the rest of the season until Dean dies battling Metatron.
- During the battle, when Gadreel rescues Dean from the other angel, the angel doesn't recognize Gadreel despite Ezekiel apparently being a well-known soldier. This may have been an early indicator that Gadreel is not who he says he is.
- This battle features the second time Dean has killed an angel with the first being Zachariah in Point of No Return. Its also only the second time that a human has killed an angel.
- In this battle, Dean kills, traps and banishes the angels he faces. While Dean has done all three before, this is the first and so far only time where all three methods of dealing with angels were used in a battle.
- While fans are left wondering if Death had really come to reap Sam or if it was just another manifestation of Sam's subconscious, Death confirms it was him in Brother's Keeper, showing that he is angry that Sam escaped his grasp.
- Dean uses the angel banishing sigil in battle again. That hadn't been seen since season 7's Reading Is Fundamental where Dean used it to banish Hester, Inias and Castiel to save Sam, Meg and Kevin Tran. It makes a brief reappearance in Heaven Can't Wait where Castiel uses it to try to banish Ephraim, but he fails. This battle is the last successful use of the sigil on the show so far.
- ↑ We Need To Talk About Kevin
- ↑ Trial and Error
- ↑ The Great Escapist
- ↑ Sacrifice
- ↑ Clip Show
- ↑ Sacrifice
- ↑ Sacrifice
- ↑ I Think I'm Gonna Like It Here
- ↑ I Think I'm Gonna Like It Here
- ↑ Devil May Care
- ↑ I'm No Angel
- ↑ Slumber Party
- ↑ Dog Dean Afternoon
- ↑ Rock and a Hard Place
- ↑ Holy Terror
- ↑ Road Trip
- ↑ Sharp Teeth
- ↑ The Purge
- ↑ Do You Believe In Miracles?
- ↑ I'm No Angel
- ↑ Meta Fiction
- ↑ King of the Damned