Sam Winchester hunts demons and supernatural creatures with his older brother, Dean.
After his girlfriend Jessica is killed by a demon, he joins his brother Dean in the search for their father who is hunting the demon who also killed their mother.
Young Sam and Dean
Sam is the second child of Mary and John Winchester and younger brother to Dean Winchester. When he was six months old, his mother was killed in a fire
when she was checking on him in the nursery but found a stranger by Sam's crib. He set her and the room on fire. John and Dean quickly discovered them and Dean carried his baby brother outside of the house. From that point on, Sam and Dean were both trained into demon hunters because their father wanted to avenge his wife's death. Sam wanted to have a normal life and left the two to attend college. He met his future girlfriend Jessica at Stanford and they soon started dating. He also saved her from Bloody Mary when her friends fell victim. However, one night Jessica was killed the same way as Sam's mother. Since then, Sam travelled with Dean throughout America in order to find their father and the demon responsible.
Sam has a vision
Throughout the series, Sam displays special powers for he is one of the 'special children' of the Yellow-Eyed Demon. These are all children who were visited
by him on the day they turned six months old. Sam starts having nightmares of events yet to come and later on these turn into visions he has while awake. He also seems to be able to move objects with his mind, as seen in the episode 'Nightmare'.
In the episode 'Rising Son', a fellow hunter warns John that Sam will one day become the leader of the army from Hell. John refuses to believe this, but does tell Dean before he dies that he must kill him if he cannot save him.
Sam's older brother. Dean always took care of Sam when he was younger when their father was out hunting. Dean was devastated when Sam left them to go to college. After their father disappears Dean comes to collect Sam in order to find their father together. Their bond only grows stronger during the amount of time they spend together. They are both willing to give up their life for each other.
Sam's father. He always felt very protective over Sam. He raised Sam into the hunting life. When Sam wanted to go to college, John told him that he shouldn't come back. And that's exactly what happened. When Sam and Dean finally find their father again, Sam accuses John of never telling them what's going on and treating them as children.
Sam's girlfriend. They met at Stanford. She is killed by the Yellow Eyed Demon right in front of Sam. He wants to get revenge for her and his mother(who was killed by the same demon).
In the original American TV-series, Sam is played by Jared Padalecki who also provides his voice in the anime.