Adam, Dean and Sam
Dean and Sam are brothers while Adam is their half-brother whom John kept away from the hunting lifestyle. So unlike Sam and Dean, Adam is not a hunter.
All three brothers are descendants of Cain and Abel, and thus, capable of being a vessel for the archangels Michael and Lucifer.
Background
Adam was born September 29, 1990 to his mother Kate Milligan. When he was 12, he begged his mother to call John. When John heard he had a son, he dropped everything (Sam and Dean remember this but didn't know why). They spent some time together but John never told him of his other children who likewise had no idea about their new brother. Years later, two ghouls with a vengeance against John kill Adam and his mother, and impersonate them in hopes of luring John into a trap, but their call to John leads them to Sam and Dean instead.
Season 4
| “ | This thing killed my mom. If you're hunting it, I want in. | ” |
— Adam
in Jump the Shark | ||
"Adam" meeting Sam and Dean
In Jump the Shark, Sam and Dean are very surprised to hear they have a half-brother. Dean becomes very suspicious, and thinks it is a trap. Regardless, they head to a diner to meet him. Dean steps up the area in case this "Adam" is a shapeshifter, or demon. Sam finds out that Adam is actually a real person through his research and confirms it further with clues from John's journal. Then Adam shows up, and Dean begins to ask him questions.
Frustrated, Dean tells "Adam" that he's not John's kid, but that he and Sam are. "Adam" is surprised that he has brothers too. To further prove that "Adam" is their brother, he shows them a photo of him and John together, something that shocks them. Convinced, Sam and Dean help Adam figure out what happened to his mother, and it isn't until "Adam" demands answers that Sam reveals (despite Dean's protests) about hunters and hunting.
"Adam" seems cool with it and even wants to partake, but Dean refuses. He points out that John wanted to protect Adam from this life, yet Sam goes ahead and teaches him some skills.
While Sam is teaching Adam, he hears something in the vents and gets Adam out of there. They head to Adam's truck, but Sam is grabbed by something from underneath. Adam rushes to help Sam, and then Dean arrives on the scene and helps. Sam suggests they use Adam as bait (much as he dislikes the idea, Dean outright refuses) and starts to train him. Sam and Adam have a brotherly bonding moment. Dean is still not liking the idea because he wants Adam nowhere near the hunting lifestyle.
Dean discovers Adam and Kate.
While Dean is out, Sam and Adam get the place ready for the creature. Then Adam's "mother" walks through the door, and Adam rushes to her. Sam quickly tries to convince Adam to step away from his "mother", but "Adam" knows this and knocks Sam out. The two capture Sam and turned out to be ghouls that reveal they are the children of the Ghoul that John killed years ago and that they wanted revenge on him so they killed people who he was close too in the town and intended to lure him back. Since John was already dead, Sam and Dean had to pay the price for his crime against their family. Adam's "mother" then taunts Sam by revealing to him that the real Adam was indeed his and Dean's brother before describing his death, to Sam's anger.
Meanwhile, Dean discovers Adam's body in the crypt before returning to save Sam. After arriving, Dean kills the ghouls, avenging Adam's death. Sam and Dean then give a hunter's funeral for the brother they never knew.
Season 5
| “ | Sam:Adam, you may not believe it, but Dad was trying to protect you, keeping you from all this. Adam:Yeah, well I guess the monster that ate me didn't get that memo. |
” |
— Sam and Adam
in Point of No Return | ||
Adam rejects Sam attempt to bond
In Point of No Return, Dean, Sam and Adam are re-united again when Zachariah brings Adam back from the dead and Cass brings him to them. When Adam wakes up, he questions who they are since it's not the same Adam they met a year ago (which was a ghoul pretending to be him) but the real Adam. Sam and Dean then inform the surprised Adam that they are his brothers, though Adam knows their names and is distrustful of them due to what the angels told him about them in Heaven. He demands to know where Zachariah is, as he tells the boys he is Michael's vessel, which surprises Dean. This motivates Dean even more to say "yes" in order to spare Adam of this fate but he is locked in the panic room. Sam later tries to reason with Adam using John, but Adam retorts that he didn't consider John as his father just a guy who took him to a baseball game once a year; nothing more. Adam then tells Sam and Dean that his mother was his family not them, as Sam responds that they need time and they have a plan. Adam asks what the plan is, and Dean remarks on the power of love being the plan. Sam just begs Adam for more time.
Dean tries to save Adam
Sometime later, Adam would try to sneak out but is caught by Sam who talks to him but once again Adam is distant towards him as Sam remarks with his attitude that he'd fit right in with the family. In a dream, Zachariah tricks Adam into telling him where he is. He tells Adam that Sam and Dean are not to be trusted while Adam shows he has somewhat trusted their word as he says they said the same about Zachariah. However, Zachariah convinces him that the Winchesters care about each other more than Adam. When Adam goes missing, Sam and Dean go after him.
They manage to find Adam (who realizes he has been tricked) who is surprised and touched they would come to his aid as Dean states he's family. Adam tries to warn Dean about Zachariah's trap, but it's too late. Zachariah easily tossed a sneaking Sam aside and begins torturing Adam and Sam so Dean will say 'yes', having brought Adam back to use as bait. Seeing both his brothers in pain, Dean caves and tells Zachariah to call Michael. When Dean notices Sam's disappointment, he kills Zachariah instead. They all attempt to escape the room before Michael arrives. Dean picks Adam off the floor and leaves him to walk on his own when Adam assures him that he's fine. Dean carries Sam towards the exit with Adam following behind.
However, the door closes before Adam can get out. Dean tries to help Adam, but he can't open the door. When he does, the room and Adam are gone. Later on, Sam and Dean are sad at failing their younger brother and believe the worse has occurred to him.
During Hammer of the Gods, Dean tells Sam that they will find Adam.
In Two Minutes to Midnight, Castiel tells Dean, Sam and Bobby that Michael is currently using Adam as his vessel, which meant Adam consented to the archangel's possession. This worried the brothers as they feel guilt for not sparing him of this terrible fate.
In Swan Song, Dean finds Michael in possession of Adam's body. He tries to speak to his half-brother by apologizing for his fate, but Michael coldly brushes him off and Dean swears to come after Michael for what he has done to his family. When Sam is about to jump into the Cage, Michael tries to stop him, but gets pulled in along with Sam. This leaves Dean to watch as both of his brothers go to Hell.
Season 6
In Appointment In Samarra, Dean tries to make a deal with Death to get Sam and Adam's souls out of Lucifer's Cage. Dean tells Death that he'll return his ring to him in exchange for their souls, but Death reminds Dean that he was only supposed to be borrowing his ring in the first place, and anyways, he knows where Dean hid it. He doesn't completely reject Dean's request, however; he tells Dean that he has to make a choice between Sam or Adam's soul. Despite trying to convince Death otherwise, Dean soon chooses Sam since his soul has been there longer, effectively leaving Adam trapped in the cage.
Season 10
In Fan Fiction, Sam and Dean visit a play based on the Supernatural books. Among the cast is a student dressed as Adam. Sam and Dean initially don't recognize who this is, until Maeve points it out. This leaves an uneasy feeling in the brothers as they recall their trapped brother.
Season 15
| “ | Adam, I want you to know... we are sorry. What happened to you... you're a good man. You didn't deserve that. Since when do we get what we deserve? Good luck. |
” |
— Dean and Adam
in Our Father, Who Aren't in Heaven | ||
In Our Father, Who Aren't in Heaven, the Winchesters bring up of what happened with Adam after deciding they have to go to Hell to get Michael. However, they learn that he and Michael are not present in Hell anymore.
With word from Donatello Redfield, they are finally able to reunite with Adam when he and Michael escape from Lucifer's Cage. When they try to explain their actions regarding Adam to Michael, the archangel relinquishes control to Adam so that they can tell him themselves. Sam and Dean are shocked that Michael allows Adam control, but Michael takes control back abruptly from Adam while they are trying to explain the situation. In turn, while Adam is still angry that his brothers abandoned him in the Cage, he tells Michael that they always try to do the right thing, including trying to prevent Adam from becoming Michael's vessel and Michael should consider what they are saying.
After getting the spell they need from Michael, Dean requests to speak to Adam again which Michael obliges. Dean apologizes to Adam for what happened to him, stating that Adam is a good man and doesn't deserve what happened to him. Adam's response is to ask "since when do we get what we deserve?" and he wishes Dean and Castiel luck before departing.
In Inherit the Earth, Dean and Sam are visibly saddened to learn about Adam being exterminated by God along with everyone else, leaving Michael alone in Adam's body, Dean sadly commenting "Poor bastard never caught a break".
Trivia
- As noted by Zachariah, Adam and Dean share similar traits, such as their shared enjoyment in eating burgers and drinking beer as well as their personality traits.
- Adam's other similarities are to his brothers is that he has a complicated relationship with their father, losing his mother, a stern attitude and he has been resurrected like them.