10 Mind-Bending Sci-Fi Movies That Will Melt Your Brain

3. Cloud Atlas (2012)

Based on the novel by David Mitchell (no, not the one from Peep Show), Cloud Atlas is - without question - one of the most ambitious sci-fi movies ever made.

It is epic almost to the point of parody, given that it consists of countless stories spread across six different time periods - some in the past, some in the present, some in the future. The concept alone, which tries to convey humanity's collective "togetherness," is about as bold as they come, and the film - by the Wachowski siblings - doesn't pander.

So it is mind-bendingly confusing from start to finish; just when you think you've got a grasp on the narrative, Hugh Grant turns up dressed as a jungle native. The film switches back and forth between time frames as diverse as San Francisco, 1973 and Neo Seoul, 2144.

In its ambition is to be vast, Cloud Atlas is also kind of laughable in places because most of the actors have been cast multiple roles: just when you thought you knew Tom Hanks, he's glimpsed here wearing questionable "yellowface" makeup. If you can forgive the awkwardness, though, Cloud Atlas is a really rewarding film (break your brain as it will).