Despite an almost-perfect 44 on his MCAT score, Ben Campbell (Jim Sturgess), must try and find a source of money to pay the extortionate entry fee to Havard Medical School. Offered a chance to apply for the Robinson Scholarship - which would pay all of his fees - he finds himself out of favour for having no 'life experience', having dedicated his life to achievements.
His Professor at MIT, Micky Rosa (Kevin Spacey), offers him a place on a card counting team where he can place his superior mathematical talent to gaining money from Vegas casinos. There, he tells the team that he is only saving enough money to pay for Med School before he is out.
Ben starts to learn though, that once you're winning big in Vegas, the little things begin to matter a lot less - and the more you win, the more attention you attract to yourself as he starts to be watched by security chief Cole Williams (Laurence Fishburne).
21 is based on Bringing Down The House, a book by Ben Mezrich and it draws from his own experience as a semi-autobiographical look at how counting cards can ruin both a casino and a promising academic talent. As a result the film takes on an accurate explanation of what card counting actually is and how the casinos are successfully dealing with it.
Of course, 21 isn't an educational film and is there to entertain. With locations all over Vegas, the lights shine brightly and, as with any casino-based crime film, the slow-mo goes into overdrive as the full effect of the glamour starts to shine through. Throw in Kate Bosworth as the lead female and 21 becomes reality of those high-rolling teenage dreams we've all had.
With all the slow-mo the film inevitably suffers in the storyline front, substituting substance for glitz and with game after game of blackjack, 21 begins to slip dangerously close - but not into - monotony. The fact that the film plays a risky game with the audience's attention somehow works and the flick between Vegas and MIT always seems to happen at the perfect moment.
Putting a relatively unrecognisable actor (Sturgess) as the lead against arguably two of the best in the game (Spacey and Fishburne) is a risk but with Spacey's character being lost under the dual identities and Fishburne being severely under-utilised the risk seems to pay off with Sturgess more than holding his own against them.
This is perhaps a film left to those with a vested interest in the gambling world or those who just want some Friday night entertainment, where for one night their teenage dreams can be fulfilled.