This is a dreadful film and an utterly worthless entry in a series that began so promisingly before it degenerated into dross. And, believe me, despite its high-end production values and workmanlike feel, this is pure, unadulterated dross.

Constructed as the third Mummy film (though in reality the fourth after the spin-off that was The Scorpion King) this is a blatantly transparent attempt to breathe life into a scraggy, desiccated carcass.

Brendan Fraser and John Hannah return for another adventure, with Maria Bello cropping up to fill the dainty boots of Rachel Weisz, who wisely bowed out.

Fraser and Bello – replete with posh accent – agree to act as couriers for a priceless diamond that the Brits wish to give back to the Chinese following the end of the Second World War.

Naturally they come into contact with followers of a long-dead emperor (Jet Li) who needs the diamond to fulfil his wish for eternal life at Shangri-La.

The excuse for a plot melds sub-Indiana Jones thrills with Crouching Tiger martial arts and a finale borrowed wholesale from James Hilton's Lost Horizon. But it all falls horribly flat.

There is not an ounce of originality in the entire picture. Fraser should be ashamed of himself. Cohen, meanwhile, will be laughing all the way to the bank.