Blackjack, so they say, is the only casino game you can win without cheating--if youíve got the kind of calculator brain that can tally a roster of when the choicest cards are most likely to appear. Itís the kind of task that sounds custom-made for an MIT grad, which works out for Ben Campbell (Jim Sturgess), a brilliant senior who wonít go to med school unless he coughs up $300,000 in tuition. Luckily, everyoneís favorite professor, Micky Rosa (Kevin Spacey), drafts him for a secret after-school club where students, like Benís pretty classmate Jill Taylor (Kate Bosworth), learn to count cards for the purpose of making money on weekend jaunts to Las Vegas. Based on the very slimmest margin of a true story about the real-life (and more Asian than depicted here) MIT Blackjack Team, 21 is less about the romance of numbers or the reality of the Vegas system--think A Beautiful Mind meets Casino--than it is a teen drama shoehorned into an extended bachelor party. The movie feels bankrolled by the Nevada Chamber of Commerce, equal parts come-on--Strippers! Shopping! Comped penthouse suites!--and loss prevention: If our facial-recognition software spots you counting cards, Laurence Fishburne will break your face. Spacey, Bosworth, and Fishburne do their same-old with dependable results, but Sturgess, who was very appealing in Across the Universe and The Other Boleyn Girl, here expresses all emotions, from worry to lust to exhilaration, by appearing seasick.