Mankind's fate rests on the hulking shoulders of action star Vin Diesel, which guarantees an inordinately high body count and several spectacular explosions before the end of the world or the end credits, whichever comes sooner.

Worryingly, the leading man's growling, one-note performance is more compelling than most of his co-stars, including the usually luminous Charlotte Rampling. Her stilted portrayal of a religious leader with delusions of grandeur elicits almost as much unintentional hilarity as the hare-brained plot.

Writer-director Mathieu Kassovitz and co-writer Joseph Simas punctuate the meandering storyline, based on the novel Babylon's Babies by Maurice G Dantec, with some decent action sequences including a high-speed skidoo chase and a brawl in a crowded club.

Diesel faces each twist and turn with his usual muscular indifference, arming himself to the polished teeth because: "You can never have enough firepower."

A mantra for life.

Mercenary for hire Toorop (Diesel) is offered one of the most lucrative contracts of his inglorious career: to escort a young woman, Aurora (Melanie Thierry), from her Neolite convent in Mongolia to New York.

Toorop accepts but is forced to alter his usual routine when Aurora's protector, Sister Rebecca (Michelle Yeoh), insists on accompanying her ward on the dangerous expedition.

While the Neolite High Priestess (Rampling) and her followers keep a close eye on Aurora's progress, the young woman's supposedly dead father, Dr Arthur Darquandier (Lambert Wilson), observes from afar, waiting for an opportunity to snatch Aurora from Toorop's grasp.

As the mercenary follows his carefully plotted route through Kazakhstan, across the Bering Strait and on to America, he enlists the services of old friend Finn (Mark Strong). They quickly realize Aurora is not what she seems. When Finn suggests that the girl may be the host for a biological weapon, and would be worth a small fortune, Toorop's resolve hardens: "If she's carrying a virus, I'll kill her myself and burn the body."

Babylon AD melds elements of The Transporter and the dystopian fantasy Children of Men, treating each leg of the journey as a self-contained set piece, including an explosion at a train station and a scramble to board a submarine before it descends beneath the ice.

While Rampling and many of the supporting cast embrace the material with deadly seriousness, Diesel at least has a twinkle in his eye, suggesting he recognises the script for the nonsense it really is. Thierry possesses a youthfulness and beauty, which holds our attention, while Yeoh, Wilson and Strong squander their talents.