If the end of humanity was nigh in a heavenly hail of fire foretold in the Bible, would anyone spare a passing thought for the fate of excessively overpaid Hollywood stars in their plush mansions?

Seth Rogen and Evan Goldberg, co-writers of Superbad and Pineapple Express, have done, and now poke merciless fun at the decimation of the US west coast in the raucous comedy This Is The End, in which the current crop of cinema's bright young things play exaggerated versions of themselves.

In the film's opening segment, Rogen shuffles embarrassed through an airport as someone asks, "You play the same guy in every movie. When are you going to do some real acting?" And at a heaving house party, Michael Cera of Juno fame is exposed as a drug-snorting, chauvinist oaf, who gladly accepts sexual favours from fans and rudely slaps Rihanna's behind.

There are undeniably hilarious moments in the ramshackle script including the appearance of a sinkhole that claims the lives of virtually the entire cast. However, there's a surfeit of ideas without clear direction, the tone lurches awkwardly from comedy to special-effects laden mayhem and the final reckoning arrives 15 minutes too late.

The film opens with Rogen excitedly welcoming actor buddy Jay Baruchel to Los Angeles, a city which Jay clearly loathes. He's less than thrilled at the prospect of attending a house party thrown by James Franco. "I will stay with you all night," Seth promises. "Nobody puts Jay in the corner."

With the booze flowing and Michael Cera harassing anything in a skirt, Jay puts on a brave face, especially when he encounters arch-nemesis Jonah Hill. In order to escape, Jay heads to a nearby grocery store for cigarettes with Seth in tow.

Then pandemonium ensues.

Bright blue beams of light scythe down from the sky and suck up hundreds of people. The buddies race back to the party but Jay immediately wants to leave, telling Seth, "I don't want to die in James Franco's house!"

This Is The End is a potty-mouthed hot mess that scores a decent amount of laughs in between homoerotic male bonding and inevitable toilet humour. Bodily fluids are tossed to and fro, and one male actor suffers a grotesque sexual assault that would be offensive were it not so outlandish. Emma Watson becomes the punchline to another rape gag, trying to keep a stiff upper lip during her cameo as she surmises, "I think it's obvious what's happening here: it's a zombie apocalypse!"

The cast appear to be having a blast and occasional smirks suggest some of the banter is ad-libbed.

That freewheeling, fun-loving attitude soaks every frame, but it also means that, like Jay, we're ultimately left looking at our watches, wondering when it's polite to leave.