Other versions of the character have been portrayed by Alex Ferris and Dylan Kingwell (child), Colin Ford (teenager), and Colton James (body switch with Gary Frankle in Season 5).
When Sam was six months old, his mother Mary (a retired creature hunter) was engulfed in a massive conflagration by yellow-eyed demon Azazel (one of four Princes of Hell).
Sam believed that his mother had died in a car accident and that his father was a traveling salesman, until the age of 8 (1991), when he read John's meticulous hand-written journal entries, describing intricate details of his hunts (as well as creature-related literature and obsessive cataloguing of demonic omens related to Azazel), compelling Dean to confirm the existence of the paranormal.
Sam started hunting alongside his brother and father at the age of 8–12, assuming increased responsibilities around the time that Dean left temporary foster care at Sonny's (1995);[11] however, he began wanting a normal life without monsters again.
[12] Throughout the rest of his teens, he continued to provide support to John and Dean, including in an advisory capacity for a kitsune hunt (1998) which he stumbled into personally in direct connection to meeting teenaged Amy Pond.
At nineteen, after a heated argument with John, Sam matriculated into Stanford University, thus finally splintering from his family and their hunting crusade, until the main story events unfolded in Season 1, pulling him back into a role of saving people.
After defeating a woman in white and discovering a trail to lead them to their father, Sam returns to Stanford where he witnesses Jessica's death at the hands of a demon – exactly the same way his mother was killed.
[20] As the boys start to take a more active role in hunting, Sam begins to search for psychic children like him to find out Azazel's plan.
With the help of fellow hunters Bobby Singer and Ellen Harvelle, Sam and Dean track down Jake, but are unable to stop him from opening a gateway to Hell on Azazel's orders.
With Bobby's help they lock Sam in a protected panic room[38] so that he can detox, but the withdrawal symptoms are painful and he begins experiencing hallucinations.
Sam hesitates when he hears his brother yelling for him, but when Lilith mocks him for his inability to do the job – even after becoming a monster to do so – he finishes her off, fulfilling his true destiny as the "special child."
He feels tremendous guilt for starting Armageddon and soon learns his acts have revealed a destiny Dean will be the vessel of the Archangel Michael to fight Lucifer.
[50] Upon arriving in Detroit, Sam begs Dean to go live a normal life with his old flame Lisa Braeden and says his goodbyes to Bobby and Castiel.
The sudden arousal of Sam's childhood memories and those of the bond of brotherhood he shares with Dean allows him to overpower Lucifer and regain control of his body.
[56][58] Upon Dean's request, Death retrieves Sam's soul from the Cage and returns it to him at the end of the sixth season's mid-season finale "Appointment in Samarra".
Sam is shown to possess great guilt about this and rejects hope that Bobby's ghost may be helping them out after an attempt to communicate with him fails.
During the final battle at Sucrocorp, Sam rescues Kevin Tran – a Prophet who can read the Word of God – and is horrified to hear of Dick Roman's plan to kill all the skinny people in the world through poison in their coffee creamers.
They find out that Kevin had managed to escape from Crowley six months ago and left Sam a string of desperate voice messages, begging for help.
Sam feels guilty and joins Dean in tracking down Kevin, who reveals that he has discovered a passage in the Word of God that would banish all demons from Earth forever.
Martin contacts Sam in "Citizen Fang" to tell him that he believes Benny killed somebody, bringing the Winchesters to Carencro, Louisiana, to help investigate.
Castiel – who has been mysteriously rescued from Purgatory – enlists his help in saving the angel Samandriel from being tortured by Crowley, forcing the brothers to reluctantly work together again.
[66] Around this time, Sam and Dean encounter their time-traveling paternal grandfather Henry Winchester and discover that through him, they are the legacies to an extinct secret society of compilers of supernatural information and artifacts known as the Men of Letters.
Although they manage to subdue the demonic Abaddon, who has pursued Henry into the present, their grandfather is killed, leaving Sam and Dean the last link to the Men of Letters.
[71] Sam is close to death in the premiere, "I Think I'm Gonna Like It Here"; it is revealed that the trials have severely burned his internal organs as well as cut off oxygen-flow to his brain, and that he has virtually no chance of survival.
They eventually manage to determine the location of a portal to Heaven that allows Castiel to trap Metatron while Dean kills Abaddon with the First Blade – acquired from Cain himself and the only weapon capable of killing a Knight of Hell – but Castiel is left dying of the grace he stole to regain his powers while Dean is transformed into a demon due to the First Blade's influence.
Sam is later reunited with his brother and mother attack the Winchesters to try to take control of America's hunters and Lucifer is left on the run trying to find a new vessel.
Stuck for options to stop Lucifer after he takes Jack's grace to charge his own powers, Sam is beaten by the Archangel until Dean agrees to act as Michael's vessel.
Chuck kills Jack and Sam shoots God who soon releases every evil spirit from hell to attack the trio in a dramatic show of frustration, with a prequel statement "Story's over.
With Chuck back at full health, he takes away whatever luck that Sam and Dean had that prevented them from experiences normal things like a common cold or toothache, as the answer a call from Garth.
Like his brother, Dean, he possesses many abilities that are frowned upon by law, including but not limited to: lock picking, computer hacking, disguised conning, and carjacking.