Movie: Star Wars Episode V The Empire Strikes Back (1980)
Writer: Leigh Brackett and Lawrence Kasdan

Back in 1980, nerds everywhere emitted gasps of disbelief. Darth Vader (David Prowse, voiced by James Earl Jones), the villainous mastermind behind George Lucas' landmark science fiction classic Star Wars, goes toe-to-toe against the heroic Luke Skywalker (Mark Hamill) in an especially tense light saber battle; Vader, getting the upper hand (literally), slices off one of Skywalker's hands.

But that's not the crazy part: In what's become one of the most universally known and admired plot twists of all time, Vader then tells his opponent that, “Luke, I am your father.” And just like that, an already epic tale of intergalactic drama evolved into a much more intimate, and ultimately tragic, story about a truly dysfunctional family.