Most recent disaster movies blame mankind for the imminent end of civilisation they predict. Not so here. It's all to do with a peculiar alignment of the Earth and the Sun as foreseen in ancient Mayan calendars. Tipped off by top geologist Chiwetel Ejiofor, the US president and leaders keep it a secret from common humanity that the Earth's crust is about to disintegrate. Meanwhile, they raise money from the world's upper crust ("People like Bill Gates, Rupert Murdoch and some rich Arabs," according to hippie broadcaster Woody Harrelson) to build arks in China and save the lives of the great and the rich, pairs of animals and the treasures of the Louvre from the oncoming flood. One suspects from the film's ambivalent tone that Halliburton got the contracts.

Queen Elizabeth II and her corgis get a berth on an ark; the Pope stays behind to perish with his flock. The spectacular special effects of Los Angeles being torn apart and Las Vegas riven asunder are astonishing but devised to be wondered at rather than to involve. Give me those five minutes of the hurricane whisking Dorothy from Kansas to Oz any day. That's the difference between magic and mechanics, true grace and laboured graphics.