DVD: 21

'21' is based on the true story of the MIT maths whiz kids who made a fortune by counting cards in Las Vegas in the 1990s.

Jim Sturgess and Kate Bosworth play two of these students, and Kevin Spacey plays their tutor, who keeps telling his protégés that they're not gambling, they're simply instituting a foolproof mathematical system. Unfortunately for the viewer, he's right. There's no risk involved, so despite all the slow-motion and the booming sound effects that the director keeps piling on, it's about as thrilling as watching someone make an ATM withdrawal.