So when she bets him that he can't lay the pious, virginal Pledge Keeper daughter (Reese Witherspoon) of the new principal before school starts, fresh sport is afoot. If he fails, he relinquishes his beloved vintage sports car. If Sebastian comes through, however, he gets the one girl he can't have - Kathryn.

And if all that suggests just the hint of familiarity, then, yes, it’s because Roger Kumble's feature debut is a contemporary take on Laclos' 1782 epistolary novel 'Les Liaisons Dangereues'. And it’s almost exciting to stumble across a movie - a teen movie, no less - positioning itself for the mass market this past summer that is so reliant on dialogue over pyrotechnics. And one that finds its thrills in the written word, no less; surprisingly, Kumble very much holds to the notion of the intervention of letters. ("Email is for geeks and paedophiles.")

Gellar and Phillippe are perfect for what are scarcely difficult roles, with him essentially reprising John Malkovitch’s turn in Stephen Frears' lauded 1988 adaptation (and, bizarrely, tossing in a dash of Denzil Washington to the mix). If you can speak these lines with sufficient authority, you can carry the picture and there is certainly an undeniable frisson in hearing Buffy talk quite this dirty. Kumble’s script is spiteful, spiky and funny but even so does lack the edge of real malice of, say, a Heathers. What it does have, however, is the ability to be both cynical and wholesome. In the sly subversion of its coda, it both has its cake and eats it.

If you’ve been paying attention you already know the plot’s arc, and the whole is admittedly about ten minutes too long, but few films in past months have been quite this much fun, either.