10 Sci-Fi Movies That Get Better The Deeper You Go

4. Groundhog Day

You might need a little convincing that Groundhog Day is a sci-fi movie, but make no mistake about it - it is, like the rest of the genre, built on that age-old, simple principle of "what if" and the fact that it's a comedy seems to gloss over its high-concept status. Almost as if we're all so familiar with it that it doesn't seem as strange and wonderful as it should.

But a sci-fi it is and even though it IS a comedy, it's also right up there with The Big Lebowski as one of the most philosophically debated movies of all time. It's a story ripe for theorising, because what it seems to accept as fact - the time loop Bill Murray ends up trapped in - requires explanation that simply doesn't exist within its limits.

That vagueness has led to many, many theories - including our own that Punxsutawney is Hell and Ned Ryerson is the devil - that, naturally have taken in religious reflection, psychoanalysis and everything in between and it genuinely does improve the film to speculate without any hope of a firm answer.