It's a terrific story: A young brainiac (Sturgess) at the Massachusetts Institute of Technology, aided by classmates and coached by a professor (Spacey), outsmarts the Las Vegas casinos. Heading there on weekends, he and his teammates win piles of cash at the blackjack tables by covertly counting cards. So why isn't 21, inspired by the true story told in Bringing Down the House, Ben Mezrich's bestselling 2002 book, juicier fun?
It's not a bad film, just an uninspired, conventional one. The movie labors too hard to establish its hero as a good guy and devise a few semi-charged jolts to toss in near the end. Ditto for the performances, which are adept but predictable. For a film all about gambling, 21 takes no chances and is the duller for it.