'21' doesn't play its cards right

Good movies about card sharks should be far more plentiful than they are. Is it because card playing is not as inherently visual as, say, pool hustling? Still, you'd think that, with all the TV hours devoted to poker, some enterprising filmmaker would figure out a way to make it all work for the movies.

Last week we had "The Grand," an improvisational mess starring Woody Harrelson about a high-stakes poker tournament. This week there's "21," based on Ben Mezrich's nonfiction bestseller "Bringing Down the House" about Massachusetts Institute of Technology students who used their card-counting skills to score millions in Las Vegas.

The film is "inspired by" the book – i.e., great liberties were taken. But the essential premise is true, and it's a doozy. If only director Robert Luketic and screenwriters Peter Steinfeld and Allan Loeb had not opted for glitz. As filmmakers, they're playing for very low stakes.

Ben Campbell (Jim Sturgess) is an math genius who wants to attend Harvard Medical School but can't afford the tuition. As a possible candidate for a scholarship, he is told that he lacks life experience – the kind, at least, that looks good on a résumé.

When he is approached by his math professor, Mickey Rosa (Kevin Spacey) to head up a clandestine coven of MIT student card counters, Ben reluctantly agrees. Before long, he is piling up the chips in Vegas.

In the film's early scenes, Ben is portrayed as such a straight-arrow good guy that his rather sudden transformation into blackjack rock star seems phony. Mickey chose Ben because the kid had grace under pressure; when Ben comes down with an attack of grandiosity and loses big, we can see it coming a mile away. The filmmakers want the audience to get juiced by the high-stakes gambling, but they also want to position the movie as a cautionary tale: Lose your cool, lose your money.

The more moralistic "21" gets, the less enjoyable it is. And the moralism is selective. On the one hand, we are subjected to scenes in which captured card counters are beaten by the casino's enforcer (Laurence Fishburne). Crime, I guess, doesn't pay (even though, technically, card counting is not illegal).

On the other hand, there are puzzling sequences like the one in which Ben lies to his overjoyed, widowed mother (Helen Carey) about winning the med-school scholarship. Luketic places so little emphasis on the ignominiousness of this moment that Ben, inadvertently no doubt, comes across as a crass jerk.

But at least he comes across as something in this scene. Most of the time he's just bland. And since Luketic doesn't do much to fill in the personalities of the other players (played by, among others, Aaron Yoo and Kate Bosworth), the vacuum ends up being filled by Spacey. Once a great movie actor, he has been coasting for years on smarm shtick. He's tolerably entertaining in "21," but he occupies center stage by default.

What must it be like for a geek genius to saunter into a casino and know he's going to bring down the house? "21" never really answers this question because the people in it are all prefabricated stereotypes.

The movie also misrepresents genius. Card counting, after all, is not the same thing as mastering superstring theory – an autistic savant with a low IQ, like Dustin Hoffman in "Rain Man," could be a whiz at it. The film doesn't even do a good job of explaining how card counting works, which is probably just as well. Even the best counters have their debacles. If you've spent money to see this film, you don't need to lose your shirt, too. Grade: C

• Rated PG-13 for some violence, and sexual content including partial nudity.