The Butterfly Effect (2004)
The Original: Evan Treborn (Ashton Kutcher) is a young man with a troubled history.
He blacks out frequently as a way of blocking out the highly stressful moments in his life, but while in college, he discovers the ability to travel back in time while reading his diaries.
But when he tries to sort his past out, he realises that each trip back makes things worse.
With Added Doc Brown: Doc, quickly realsing that Evan is quite the most annoying time-traveller in the history of chrono-jumpers and decides to do the world a favour.
Gunning the DeLorean, Doc runs over Treborn's dad and Evan is never born.
Risk To The Space/Time Continuum: The world is a happier place without the Butterfly Effect story and Doc is hailed as a hero.
Next: Lost In Space