The “Back to the Future” trilogy is famous for introducing mainstream audiences to the concept of temporal paradoxes and alternate timelines. A lot of this is thanks to the film’s main protagonist Marty McFly (Michael J. Fox), who drives a DeLorean time machine back to 1955, screws up his parents’ first meeting, and nearly prevents himself from being born.
As if this wasn’t bad enough, Marty next travels to the future and buys a sports almanac, hoping it’ll help him place some winning bets. Instead, he inadvertently helps creates a dystopian 1985 that ruins hundreds of lives.
Thankfully, while Marty may constantly screw-up the time stream, the time machine’s inventor — Emmett “Doc” Brown (Christopher Lloyd) — is always there to set things right. While Doc did make a potentially fatal mistake with some plutonium and Libyan terrorists, his mind is still second-to-none at fourth-dimensional thinking.
It’s a past version of Doc who helps Marty get back to the future despite having minimal knowledge of time machines. It’s also Doc who explains to Marty how the alternate 1985 was created and develops a plan to erase the corrupt timeline.
Granted, Doc worries he may have seriously damaged history when he falls in love with doomed school teacher Clara (Mary Steenburgen) in “Back to the Future Part III” (1990), but everything turns out okay. He might fret about breaking the space-time continuum, but when it comes to time travel, few people are better suited for the task than Doc Brown.