9. What The Hell Did We Just Watch? - Donnie Darko
The Cliffhanger: To be fair, Donnie Darko is one big WTF, and its cult status is in many ways defined by the fact that nobody really seems to know for sure what it all means. The movie, about a high-schooler outcast named Donnie Darko (Jake Gyllenhaal) who encounters a series of bizarre doomsday visions, involves subjects such as time travel and parallel universes, yet Richard Kelly intentionally keeps the film's explanation extremely vague.
The Answer: Richard Kelly actually did compile parts of the fictional book that appears in the film, The Philosophy of Time Travel, and this goes a way to explaining quite what we saw. In layman's terms, on October 2nd, a Tangent Universe (the world we see in the film) is created by an unexplained temporal blip, just before the appearance of the jet engine in the movie (called the Artifact), which kick-starts a causal 28-day time loop. The Tangent Universe is unstable and threatens to destroy the Primary Universe, and it can be rectified by the so-called Living Receiver, Donnie. Anyone who dies in the TU becomes The Manipulated Dead (the guy in the grotesque rabbit suit, Frank, and Gretchen), with a subtle ability to manipulate the Living Receiver, while any living people are subconsciously urged to help Donnie accomplish his destiny, which is to die by the hand of the Artifact and bring things full circle. Hence, the jet engine killing Donnie at the end of the film destroys the TU and restores order to the Primary Universe, where Gretchen and Donnie had never met. Or something. Alright, that was a mouthful, but at least Kelly bothered to
try and explain himself, even if he ultimately raised more questions...