Les Liaisons Dangereuses, Playhouse Theatre, London

Children playing at adultery

Tim Fywell has certainly hit on a novel way of distinguishing his production of Christopher Hampton's play from Howard Davies's unforgettable hit of 1985. One might call this the Bugsy Malone version of Les Liaisons Dangereuses, but, not having seen the film in question, I may be doing its actors an injustice. They may have had more pathos and conviction than Fywell's youthful cast, who certainly give the impression of a lot of children who have raided the dressing-up box.

Though I haven't noticed an outbreak of unstoppable altruism under Thatcher's successors, the idea has been mooted that Les Liaisons Dangereuses, a product of the Eighties, greed-is-good era, may seem dated. That's not the case. This stately pavane of sex and death remains as seductive as ever it was, with plenty of lines to make you laugh or gasp or both at once. "Remember," says the Vicomte de Valmont, warning off the Marquise de Merteuil from their nasty game, "I'm better at this than you are."

"Perhaps," she says, "but it's always the best swimmers who drown." The notion of a well-born man bedding a woman to amuse himself or his friends is not as scandalous to us as it was to readers of the original Choderlos de Laclos novel of 1782. But even to those who were never great believers in sisterhood, the spectacle of a lady arranging for an innocent young girl to be raped in order to annoy the girl's suitor remains a shocker. The book burns, said Baudelaire, like ice.

When I saw the original production, I thought Hampton had gone soft on the marquise in allowing her to escape the fate she suffers in the novel - exposed, disgraced, her face destroyed by smallpox. Now, however, her going on with the game, with reputation and beauty unscathed, seems truer to the spirit of the story than the ending Laclos probably wrote so he could claim (most unconvincingly) that Liaisons was a moral tale. Its fascination, of course, lies in the use of the admired but often belittled qualities of cleverness and charm as instruments of evil.

But who embodies these upper-class monsters? Polly Walker, whose inspiration for the role seems to have been Joan Collins (heavy eyeliner, hands on hips, saucy ringlets, wide smiles), is spoilt and petulant rather than blood-freezingly cool, and one never believes that she has the intellect and steel to formulate the cruel plan. Jared Harris is likewise immature as Valmont, her accomplice, a man whose latent sexual power is meant to be obvious and terrifying. Harris's voice is flat and thin, and his mouth is often screwed into an expression that is presumably intended as blasé but looks as if he's thinking: "Not sprouts again!"

In common with so many young actors, they have no sense of the formality and reserve that characterised bearing and gesture in past centuries - a lack particularly harmful in a play whose main characters are apparently irreproachable waxworks in a Madame Tussaud's in hell. The play needs gravity and stillness to contrast with the depravity of the action, but the proud vicomte repeatedly skids across the stage to land on one knee at a lady's feet, like an eager chorus-boy.

As the marquise's lover, who is meant to be youthfully enthusiastic, Laurence Penry-Jones is far more convincing but seems too weak to reach the extremes to which his character is driven. And, as the virtuous but vulnerable Madame de Tourvel, Emilia Fox seems to equate goodness with gaucherie. Her head is often at an awkward angle, and when she tells Valmont to be satisfied with her friendship, she sounds like a scolding schoolmarm. Add to that a harshly lit and underfurnished stage, and you have a production worth seeing only for the play itself. If you haven't seen it before, though, that's enough.

To 27 March (020-7369 1785)