Traumatized by her mother's death in a car crash, college student Sara (Carly Pope) participates in a riddle game, scouring Toronto for spray-painted questions and discussing the puzzles with comic book store owner Vern (Adrian Paul). When Sara and Vern receive separate invitations to participate in a higher-stakes version of the game, they are thrilled. But after Sara's friend Jeremy (Jay Baruchel) is killed, she suspects a dangerous connection between his death and her puzzle-solving.