17. Back to the Future (1985)
Being forced to take your sister to the prom for lack of any other options is one thing. But taking your mom to her own prom so that she and your dad can fall in love, get married ,and ensure your future existence? That's something you'll likely only ever find in this '80s classic, where teenage time traveler Marty McFly (Michael J. Fox) is forced to rewrite the history of his parents' (Lea Thompson, Crispin Glover) high school romance.
The only problem? His mom's kind of into him. But all works out when Marty escorts his mama to the Enchantment Under the Sea dance; not only does he save the day—and his own life—but he gets the chance to introduce the world to rock 'n' roll.