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

1. Primer (2004)

Trying to get your head around Primer is the cinematic equivalent of trying to find a needle in a haystack; Shane Carruth's immensely impressive, super-low budget time travel movie is about as complicated as is possible for a film in this sub-genre to be. Extensively planned out by its director, writer and lead actor to a point of insane meticulousness (indeed, there was only enough film to shoot each scene once), Primer will break your brain.

The plot hones in on two friends who invent a time machine in their garage, and what happens when they tamper with the intricacies of time. Much of Primer focuses on the break-down of its lead characters' mental incapacity to deal with time travel, but there's a huge emphasis on the physics of time travel and its complex, looping structure.

Indeed, it's the sort of movie you can watch twenty times and still have no real idea as to what's going on unless you consult a chart. Admittedly, it feels more like a moving puzzle than a film at some points, but it's still probably the best indie time travel flick ever made. Certainly, this isn't the sort of movie to sit down to on a lazy Sunday afternoon.