Sam Winchester (series star JARED PADALECKI) has done his best to escape his family's eerie history. Unlike his older brother, Dean (series star JENSEN ACKLES), Sam rejected their father's obsessive quest to uncover the evil forces that claimed the life of the boys' mother. Putting as much distance as possible between himself and his family, Sam left home right after high school and went away to college. His new life includes a beautiful and loving girlfriend and plans to enter law school. Dean, however, took a very different path, following their father into the "family business." When Dean arrives on Sam's doorstep with the news that their father has vanished, Sam has no choice but to put his personal plans on hold and join Dean on the road.

After four years apart, the reunited brothers are getting to know each other again, and their familiar sibling rivalries are never far from the surface. Despite the strange childhood they shared, these boys turned out to have very different views of the world. Dean still idolises his father and, although he often appears cocky and fearless, in reality he is haunted by memories of his mother's violent death. Sam was too young to remember the awful night that their mother died and has never fully accepted the frightening path his father and brother have followed.