First Night: New Boy, Trafalgar Studios, London

This new boy on the block is touted as "Hamlet for the Skins generation", and since the lead character, Mark, is played by Nicholas Hoult from E4's "edgy teen drama", the claim is not unreasonable. As Mark starts at a new sixth-form, he is genuinely mixed up, mostly about his own sexuality.

Hoult, a rangy lad who has shot up since he played opposite Hugh Grant in About A Boy, is first seen struggling with the concept of female genitalia in a blackboard diagram – not the most hetero-friendly opening to a show I've encountered lately. But as floppy, spotty Mark he is soon wrestling with his locker-room crush on Gregg Lowe's handsome Barry – a carefree virgin everyone wants to have fun with, especially the married French mistress Mrs Mumford.

After Mark fails dismally to schmooze a real live doll on a dancefloor – and punches her in the vagina – Mrs Mumford clears the stage and addresses the classroom (that's us, the audience). This is the best passage of the play, adapted by Russell Labey from a William Sutcliffe novel, because it involves the comedian Mel Giedroyc, of Mel and Sue fame, recounting her own liberation in pupil-seducing sex as a bored housewife. Her class on Jean-Paul Sartre ("hell is other people") soon melts into a more specific address on the charms of existential shagging.

It's a classic revue sketch and the play then has to regroup around it as we learn that Mrs Mumford loses her job, Barry is expelled and the plot accelerates with the sudden incursion of convenient siblings. Barry falls in love with Mark's brother Dan (Phil Matthews), while Barry's sister Louise (Ciara Janson) sets her sights on Mark as an experimental favour. "I'm not a fag hag," screams Mark, followed by: "What's a fag hag?"

Although it's quite a short play, this endless harping on stereotypes with little perception of sexual curiosity and adolescent hormonal activity is wearing and finally tedious. The nasty edge persists in Portnoy-style references to milk bottles full of chopped liver and shrivelled private parts.

The best thing I've seen Hoult do was play a young psychopath in one of the recent Wallander stories with Kenneth Branagh, where his propensity to focus in a scary way was much better indulged than in this floppy frippery. In some ways he is like another Ben Whishaw, and it will take a more demanding text and production than New Boy to reveal his true potential as a stage actor.

In the coffin-like confines of the Trafalgar's small studio, Hoult will no doubt satisfy the yearning of Skins fans coming up close and personal to their temporary idol. But as a rite-of-passage drama, New Boy is fairly ordinary, and not a patch on Julian Mitchell's Another Country – the play that made stars of Branagh, Colin Firth and Rupert Everett.