>>176661Because Donnie Darko stayed alive, everyone around him started to die, or had their lives ruined. His mom died on the plane crash, his little sister on the plane crash, he shot Frank, the pedophile would be exposed, his english teacher loses her job, Gretchen gets ran over. So, he reads that crazy ass book and learns how to time travel through those worm holes he hallucinates about; he reads he needs a vehicle of metal to travel through the portals. A time portal opens above the city, the plane carrying his mother and sister and sparkle motion loses it's engine, which goes back in time, somehow donnie goes back in time, donnie decides to die to prevent everyone else from dying, he's a hero.