Writer-stars Simon Pegg and Nick Frost play nerdy British sci-fi fans touring Ameirca’s UFO hot spots.

In this genial, very funny comedy and affectionate send-up of Steven Spielberg’s E.T. The Extra Terrestrial, they run into a pot-smoking, beer-drinking alien (voiced by Seth Rogen), who has just escaped from a top-secret government facility.

The Brits, joined by Kristen Wiig’s naïve Christian, agree to help him in his quest to return home, but first they must outrun and outwit a trio of federal agents.

The gags come thick and fast, as do the fanboy in-jokes and geeky film references.

Rogen is a hoot as the foul-mouthed alien and there are some great cameos, too – look out for an actress famed for an iconic sci-fi role and, yes, a certain esteemed director.