Adam Milligan is the son of Kate Milligan and John Winchester, and younger half-brother to Dean and Sam Winchester. He also served as the vessel of Michael when Dean refused to accept him. After Sam successfully seals Michael, Lucifer, Adam and himself in Lucifer's Cage, Sam is eventually resurrected by Castiel, but Adam was left behind with Michael and Lucifer.
Adam was the third son of John Winchester and the half-brother of his sons Sam and Dean. Unlike his half brothers, Adam was not raised in the life of a hunter but was still a lot like Dean in personality. Though John would occasionally appear to spend time with Adam, Adam never considered him his father.
In January 1990, Adam's mother met John Winchester in Windom, Minnesota when he came into the hospital where she worked as a nurse, when he was injured during a hunt. Adam was born on September 29, 1990. That same year, John killed a ghoul. He didn't have any contact with John until he was twelve.
After the initial meeting, he had sporadic contact with John who taught him pool and poker, took him to ball games on his birthday, bought him his first beer when he was 15 and taught him to drive in the Impala. In 2009 he was studying pre-med at the University of Wisconsin.
Years later, seeking vengeance, the ghoul's children killed Kate and Adam Milligan and assumed their forms, hoping to lure John into a trap as vengeance for their father's murder at his hands nineteen years earlier.
Like Sam and Dean, Adam is tall and wears layers of clothes. He stands at about 6'0 to 6'1, with dark blonde hair and strands of lighter blonde. Adam has long hair on the back of his neck like Sam does, while he has short hair (exposing his forehead) like Dean does.
In "Jump the Shark", "Adam's" call reaches Dean and Sam instead, as John died two years earlier. Dean and Sam discover the trick, kill the two ghouls, and burn the body of the brother they had never known. Dean says he was their brother and died like a hunter, so he deserved the funeral of one.
In "Point of No Return", whilst enjoying eternity in his own private Heaven (making out on his Prom night) Adam is approached by Angels who offer him the opportunity to help the Archangel Michael defeat Lucifer by becoming Michael's vessel. Adam accepts and is resurrected under Zachariah's supervision. He awakes beneath the ground where his funeral pyre was held and crawls to the surface to find Castiel waiting for him, the angels originally meant to greet him lying dead nearby. Castiel teleports an unconscious Adam to Bobby Singer's house, much to the amazement of Sam and Dean.
When he regains consciousness, Adam informs the Winchesters of his deal with the angels and his intention to say "yes" to Michael. However, Castiel engraves Enochian runes on his ribs to keep the angels from locating him. Though they are confused as to how Adam can qualify as a vessel for Michael, Castiel deduces that because Adam is of the Winchester bloodline, he is eligible to contain Michael's essence, despite the prophecy that foretells Dean as the one and only candidate. However, Dean doesn't want him to share that fate and slips away.
Sam leaves Adam in Bobby's care while he searches for Dean. Meanwhile, Adam dreams of the park his mother used to take him to when he was little and is greeted by Zachariah, who convinces Adam that the Winchesters are not to be trusted and that if he cooperates with the angels he will get to see his mother again. Adam is initially doubtful, seeming to have started trusting his brothers somewhat, but agrees at the promise of seeing his mother again. Adam gives Zachariah his location and the angels promptly snatch him out from under Bobby's nose.
They take him to the Green Room where they had imprisoned Dean (which Dean refers to as the "Beautiful Room") and Zachariah reveals that he has been lying to Adam all along. Adam's sole purpose is to lure Dean into a position where he would have to say yes to Michael, which proves successful when the Winchesters arrive to rescue their brother, surprising Adam, as he didn't think they'd really come. Zachariah tortures Adam and Sam until Dean agrees to becoming the vessel, but this is a ruse as Dean provokes Zachariah into letting his guard down and uses the chance to stab him with an Angel Blade, killing him instantly.Dean and Sam escape the room just as Michael descends but the door slams shut behind them, trapping Adam in the room with Michael's true form. Dean smashes the door open to find the room gone, along with Adam and Michael.
In "Hammer of the Gods", Dean tells Sam that they will find Adam.
In "Swan Song", Michael, in Adam's body, faces off against Lucifer in Kansas. When Lucifer tries to convince Michael to join him and rebel against Heaven, Michael refuses and prepares to fight his brother until Dean loudly enters the cemetery in the Impala. Upon seeing Michael in Adam, Dean says "Adam, if you are in there somewhere, I am so sorry," but Michael replies by saying "Adam isn't home right now." This causes Dean to tell Michael he's coming after him next.
Before either archangel can act, Castiel uses a molotov cocktail of Holy Fire on Michael (and indirectly, Adam), banishing him from the cemetery for a time. Lucifer then destroys Castiel for this act. As Sam regains control of his body and is about to jump into Lucifer's Cage, Michael tries to stop him and both end up falling in. Despite Sam's release from the Cage, Adam is still trapped with Michael and Lucifer.
In Appointment In Samarra, Dean tries to make a deal with Death to retrieve both Sam and Adam's souls from Lucifer's Cage, but Death says that Dean can only pick one. Dean picks Sam, inevitably leaving Adam trapped in the Cage with Lucifer and Michael, where he remains now.
In Fan Fiction, Marie's stage play of Supernatural included a student dressed as Adam as he and others sung "Carry on my Wayward Son". Sam initially didn't realize who the student was imitating until Maeve told them and reminded them that he was still stuck in the cage, leaving an uneasy feeling with them.
Adam is a lot like Dean. Just like Dean, he is a "ladies' man". He is very sarcastic, sometimes rude, and laid-back most of the time. He even uses some of Dean's sayings such as "rat's ass" and "unbelievable". He is shown to hold resentment towards John for never properly being there for him, and was slow to warm up to his half-siblings; he was surprised that they cared so much for him and that they tried to save him from Zachariah. Adam was more accepting of fate and destiny as he was very willing to say yes to Michael even knowing that his fight with Lucifer could be catastrophic, something not shared by his brothers.
- Season 6
- Season 10
- Fan Fiction (Referenced only)
- Season 11
- The Devil is in the Details (Sam's flashback caused by Lucifer)
- Adam's birthday coincides with the traditional date of the Feast of Saint Michael, or Michaelmas.
- Adam was twelve years old when John Winchester made contact with him. Mathematically, this would be the same year Sam Winchester left home for Stanford. This could also indicate that John pursued a father-son relationship with Adam to fill the void that Sam leaving made.
- He is currently sealed in Lucifer's Cage, along with the archangels Michael and Lucifer and formerly Sam. It is speculated by multiple characters that Adam is being tortured by the archangels out of boredom and a lack of anything to vent their anger on. However it's possible that he is simply still possessed by Michael in Hell.
- The back of Adam's head was shown in a flash-image during the Season 8's "Man's Best Friend With Benefits", when Spencer Wallis hit Sam with images from within Sam's own mind.
- Zachariah notes that Adam and Dean have the same "palate", which is burgers and beers.