ABOUT halfway through this pedestrian action romp, Arnie self-mockingly utters "I might be back".It's symptomatic of the whole sorry mess - uncertain, wobbly and erratic.

Under director Roger Spottiswoode, Schwarzenegger flits between self-parody and the Terminator-style swagger with which he made his name, resulting in a film that masks a solid, if not exactly original, central idea with a smokescreen of trepidation.

It's set in the near future where cloning technology is part of everyday life. Your beloved pet's died? No problem, RePet will bring Rover back from the dead as a clone. Need a new kidney? Don't sweat it, Replacement Technologies can create a bespoke organ to your exact specifications. However, fully-fledged human cloning is banned.

When chopper pilot Adam Gibson (Schwarzenegger) is chartered to fly the head of Replacement Technologies, Michael Drucker (Tony Goldwyn) on a skiing trip, he is unwittingly drawn into a frightening world of murder, high-level corruption and hi-tech deception.

In essence, there has been a 6th Day violation - man has created man in his own image and Gibson is it. Having switched places on the ski mission with his pilot partner Hank (Michael Rapaport), Gibson has been successfully cloned by Drucker's boffins, led by kindly Doctor Weir (Robert Duvall). He gets home to find his life, his wife, his daughter and even his dog have been taken by another version of himself. He wants his life back.

It's an intriguing premise and makes one or two attempts to get under the skin of its own possibilities. Duvall is the pioneering scientist willing to turn a blind eye to the moral dilemmas his work throws up, while Goldwyn is suitably smarmy as the megalomaniac business tycoon only too happy to play God. The problems lie in the array of cartoon baddies and with Arnie himself - he simply doesn't have the panache to pull off the quick one-liners any more, instantly neutering any comic potential, however obvious it might be.

You can forgive The 6th Day up to a point, as the big fella still exudes a certain on-screen charm, but Spottiswoode's direction is so lumpen that it doesn't take long for the whole thing to get on your nerves.

Whilst he is in the biblical mood, perhaps Arnie should take heed of the seventh day ... and have a rest.