Beating the system—especially when the means of beating it is perfectly legal, and the results can mean big money—is an intriguing premise. Exhilarating. Even tempting. That’s what’s on the table for M.I.T. senior Ben Campbell (Jim Sturgess, Across the Universe), a 4.0 GPA math and statistics whiz, longsuffering hard worker, and notoriously poor sap with no way to pay the $300,000 he soon must shell out for his forthcoming foray at Harvard Medical School. Relax, Ben, help is on the way.

Enter charismatic M.I.T. prof Micky Rosa (more than ably personified by Kevin Spacey despite the goofy Mafia-esque name). Rosa likes Ben’s steel-trap mind and invites him to join a card-counting team that promises way more money, way sooner than Ben ever could ever earn as a doctor. Throw in Ben’s would-be love interest (Kate Bosworth), a pair of his left-in-the-dust M.I.T. buddies, his widowed mother, and the bright lights, glitz, glam (and even danger) of Vegas, and you have the makings of a cool flick.

While 21 doesn’t quite rise to "cool" status (some important storylines are left half baked; others get too much screen time), there are quite a few teachable moments. The most obvious is the Faustian scene where Spacey’s professor successfully lures Ben into the world of easy big money, despite Ben’s initial hesitations—a great illustration for temptation (and how not to deal with it). Another is a later clip in which Ben reveals he’s acquired more than the $300,000 he needs for Harvard med but still elects to play Vegas—an ideal clip for illustrating greed, as well as how it can change a person’s goals, values, and even personality.

Ben’s deteriorating relationship with his longtime friends (and its reconciliation) is a fine look at brotherhood and forgiveness. As you might guess, Ben’s skill and good fortune hold out for only so long, and there are a few twists and turns by the flick’s final frame, both effective devices—but I hesitate to recommend 21 for a youth group night out. It’s a bit too lengthy, and there’s too much of what lends Vegas its "Sin City" moniker flying around the screen, despite the handful of meaningful moments. Instead, wait 'til 21 hits the DVD racks and pull the clips you need. It’ll be worth the rental fee if your thematic agenda coincides with what 21 delivers.