21 (12A)

Blackjack is the game of choice in this glossy if by-the-numbers drama from the director of Legally Blonde.

A batch of maths whizzes, led by their professor (Kevin Spacey) take on the house in Vegas, where the group attracts the attention of Laurence Fishburne’s security chief.

As a tough guy Spacey is more smarmy than menacing, but he does lend the film the dazzle it needs to survive a dull middle section.

No matter how many special effects are deployed, seeing people play cards is up there with watching a tortoise attempt Everest.

In common with this week’s Leatherheads, 21 is another film that overstays its welcome – but like George Clooney’s latest, this film – based on Ben Mezrich’s excellent Bringing Down The House – is not without its pleasures.

The book is the story of how half-a-dozen maths geeks took the Vegas casinos to the cleaners, and relies a lot on the mechanics of card-counting and probability theory. As such it’s an entertaining read, but just about unfilmable. The solution is to stick to the spirit of the book and come up with a sentimentally predictable story.

Rising Brit star Jim Sturgess is the maths whiz who continually knocks back his fellow students and their pleas to join their Vegas scam, a wheeze that is, incidentally, the brainchild of wily professor Kevin Spacey.

But with his mother’s medical bills rising and the entreaties of Kate Bosworth too hard to resist, our boy decides to join the gang and soon becomes their star player.

The money of course, changes him: he’s horrible to everyone, and his mother doesn’t matter anymore. He also comes to the attention of casino detective Laurence Fishburne, who suspects something is afoot.

It’s glossy and stylish and will do no harm at all to the Stateside reputation of Sturgess, but ultimately 21 is too long and too predictable to be really satisfying – even though it is an entertaining enough journey.