Michael Boyd, the Royal Shakespeare Company's artistic director, has hit upon a brilliant method of wasting loads of money and talented actors' time while creating abysmal theatre. Anthony Neilson's God in Ruins is the grim result of testing this theory in dramatic practice. Boyd's notion stems from his belief that the relationship between actors and writers can be "reignited" if both parties engage in mutual nourishment in private - the ridiculous phrase is his. Accordingly, Neilson, as both writer and director, was given 11 male actors for several months to help him devise a play, the script of which Boyd had not read, let alone approved, before the programme for God in Ruins was printed.

The ensuing farcical comedy drifts between dream and reality, as if in debased homage to Neilson's own fascinating work The Wonderful World of Dissocia. The clichéd hero, an amalgam of contemporary character flaws and foibles plunged into an aimlessly wandering plot, is given a familiar crisis at Christmas. How can Brian Doherty's alcoholic TV producer of such low-grade reality shows as Chimp Monastery and Pimp My Pooch survive when estranged from his wife, missing his daughter and craving drugs?

Neilson's vignettes of alcoholic despair, whether verbal or situational, strike gross, embarrassing notes. There are neither insights nor insightful, surreal leaps of imagination when Doherty's alcoholic hero summons up the ghost of his long-dead father and travestied scenes from Dickens's A Christmas Carol.

Whether the producer is mocking his homosexual, wheelchair-bound business partner, proposing a series called Guantanamo Gay or confessing, in the style of Patrick Marber's hero in Closer, that he assumes a female identity in internet chat rooms, he remains too trivial, shallow and pantomimic to be taken as a useful immorality figure.

There are disconcerting signs, one of which involves a squaddie back from Basra, that Neilson loses track of his plot just as the producer does of his life. Only when this anti-hero joins an Encounter Group where Mark Theodore's humane actor offers him non-judgmental sympathy does a liberating solution loom. "I think I have never been who I really am," the producer says, hinting his troubles spring from that tired old phenomenon, latent gayness. Shamefully bad.

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