The film centers on an outcast teen genius named Peter Parker, who develops spider-like superhuman abilities after being bitten by a genetically-altered spider. After his foster father/uncle is murdered by an armed felon, something of which he felt partially responsible, a guilt-ridden Parker is later driven to use his new abilities for a nobler purpose, as the hero/vigilante Spider- Man, to atone for his uncle's murder. The rest of the film focuses on Parker's efforts to balance his personal life as he graduates from high school and becomes a freelance photographer, while also struggling with his studies, his friendship with his childhood best friend Harry Osborn, his growing feelings for his former high school crush Mary Jane Watson, and his dual life as Spider-Man. It is the first installment in the Sam Raimi directed Spider-Man trilogy.

References:
https://en.wikipedia.org/wiki/Spider-Man_(2002_film)