You know a film is going to be somewhat druggy when its tagline is "The ultimate trip". Indeed it is. Stanley Kubrick's epic sci-fi explores space and the dangers of technology while building to an increasingly surreal coda. This would've been a hard film to pitch to studio executives.

The main reason why a lot of people flocked to see it was because of its groundbreaking special effects and the brilliant teaming of the silence of space with stirring classical music playing over the top. It's said that this film may be describing the dawn of man.