In Toronto, 22-year-old Scott Pilgrim is a bass guitar in Sex Bob-omb, a floundering garage band. To the disapproval of his friends and younger sister Stacey Pilgrim, he is dating Knives Chau, a 17-year-old high-school student. Scott meets an American Amazon (company) delivery girl, Ramona Flowers, having first seen her in a dream, and loses interest in Knives, but doesn't break up with her before pursuing Ramona. When Sex Bob-Omb plays in a battle of the bands sponsored by record executive G-Man Graves, Scott is attacked by Ramona's ex-boyfriend Matthew Patel. Scott defeats Patel and learns that, in order to date Ramona, he must defeat the remaining six evil exes.
Scott Pilgrim meets the girl of his dreams, Ramona Flowers, but learns he must defeat her seven evil exes in order to date her. Then things get even more complicated.
