21, 12A

The stakes aren't high enough in 21. It's based on the true story of the MIT maths whizz-kids who made a fortune by counting cards at Las Vegas blackjack tables in the 1990s. Jim Sturgess stars as a diligent student who is recruited and trained by one of his tutors, Kevin Spacey, and catapulted into a world of designer suits and swanky hotels. Spacey keeps telling his protégés that they're not gambling, they're simply instituting a foolproof mathematical system.

And, unfortunately for the viewer, he's right. There is no risk involved, so despite all the slow-motion and the booming sound effects that the director piles on, it's about as thrilling as watching someone make a withdrawal at a cash machine.