Ben Mezrich's 2002 book about the MIT Blackjack Team, "Bringing Down the House," told the story of a radically extracurricular after-school activity. From about 1980 through 2000, a shifting band of Ivy League math brainiacs, using intricate card-counting strategies, managed to relieve the casinos of Las Vegas (and eventually Europe) of millions of dollars playing blackjack, or 21. The team was real, but Mezrich's account of it was entertainingly embroidered. Now, "21," the new movie based on his book, has taken so much more dramatic license with the tale that it might be best to ignore the picture's "inspired by a true story" ad line and just enjoy it as a lively variant of the classic heist movie.

Jim Sturgess, the young English actor most recently seen in "The Other Boleyn Girl" and "Across the Universe," here deploying an American accent that might draw an approvingly cocked brow from Hugh Laurie himself, has the unusual ability to project contemplation and reticence as star qualities, and his quiet magnetism anchors the movie. Sturgess plays Ben Campbell, an MIT math wiz who's worried he won't qualify for the scholarship he needs to attend Harvard med school, and who doesn't have the $300,000 necessary to do so otherwise. Fortunately, a sardonic MIT professor named Micky Rosa (Kevin Spacey) has an opening on his hush-hush blackjack team — a group of student card counters whom he rigorously trains and then leads on weekend trips from Boston to Vegas to beat the casinos big-time, and repeatedly, at 21. (Blackjack is the only casino game in which that's possible.)

The team's late-night practice sessions, held in empty, out-of-the-way classrooms, have the conspiratorial intensity of anarchist bomb-maker meetings. Ben is quickly attracted to the smart, pretty Jill (Kate Bosworth), who learned blackjack from her gambler father; but his superior counting skills soon alienate the egocentric Fisher (Jacob Pitts), who resents being displaced as the team's top player. Director Robert Luketic ("Legally Blonde") knows there's no way to convey fully the anesthetizing complexities of card counting in a movie, so he does the smart thing — he finesses them. We learn about the basics of the team's operation — about "spotters," for instance, the team members who quietly count the cards at a table, waiting for the deck to get "hot" (with a preponderance of high-value cards), and then signal their heavy-betting confederates to move in for a kill. But the convoluted techniques of counting cards are dispensed with in a glittering montage that has the appearance of being informative without overloading us with too much actual information. (The movie's stars and real-life card counters explain their technique here.)

Fortunately, this doesn't matter. The movie is really about the liberation the students feel in Vegas, where Professor Rosa — who runs the team strictly as a business, one that's never to be talked about back home — gives them new identities (down to bogus accents and false mustaches) and, at the end of each night, bundles of cash beyond their wildest imaginings. We see them sailing down the Strip in open-top limos and floating through high-end strip clubs on a river of champagne. "In Boston we had a secret," Ben says, looking back later. "In Vegas we had a life." Then he adds, "It was too good to be true."

Casinos hate card counters, of course, especially in teams, and the MIT kids' nemesis is a casino security chief named Cole Williams (Laurence Fishburne). Williams is part of a fading breed — a pro whose years of experience enable him to spot counters using only close observation (from his eye-in-the-sky post up above the casino floor) and gut instinct. But now there's new biometric face-recognition software being introduced in the casinos, and he knows this will soon put him out of a job. (It will also put the MIT team out of business.) Williams' current casino is one of the last to employ his services, and he's very, very serious about providing them. ("If I ever see you here again," he says, after busting one team member, "I will break your cheek bones with a hammer, and then I will kill you.")

The picture's dynamic thus has a gratifying familiarity: a complicated caper and a tense chase leavened with humor and romance. (One love scene, played out before the panoramic windows of a high-roller hotel suite, with all of Vegas ablaze below, evokes more of the allure of the place than many whole movies about it.) We may not buy Williams' over-the-top viciousness, or the film's hyper-elaborate triple-cross conclusion, but it's a picture that's pleasurable to give in to and go along with. The editing is tight and vigorous, the images have a seductive gloss (the cinematographer was Russell Carpenter, who also shot "Titanic"), and Spacey's trademark deadpan nastiness hasn't been quite this enlivening since "Swimming With Sharks."

Spacey is also one of the movie's producers, and it was he who picked Sturgess to star in it. This might be an intergenerational salute from one idiosyncratic actor to another — although Sturgess, if only because of his attractively tousled appeal, would seem likely to have a larger career as a romantic lead lying ahead of him. Like Spacey, though, he has serious technical skills as well, and his performance here is aces.

Read Kurt Loder's new review of "Flawless."

Check out everything we've got on "21."

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