I rely on Philip Ridley to leave me shaken and shocked. His considerable imagination reaches places I prefer not to visit, unless escorted by a writer of his moral seriousness.

The memory of the dystopian horrors of his last play, Mercury Fur, a ghastly melange involving gay snuff movies shot at rich men's parties in a post-apocalyptic London, haunts me still.

His latest work, which rakes over familiar Ridley terrain and deals with sexual and psychic damage done in childhood, marks a regression, even though the suspense of the slightly Pinteresque plot exerts a tantalising hold.

Leaves of Glass is embroidered with the melodramatic apparatus of ghosts, bombs and nightmares, which seem sensational rather than essential.

Contrived in form, repetitive in structure and half an hour too long, it speaks in such periphrastic, discreet allusions to paedophilic sex that it might have been written ages ago when plays were still censored.

Ridley portrays the lives of two dysfunctional East End brothers in their twenties, who have long kept their silence about a shared sexual secret. Ben Whishaw's tense and edgy Steven runs a graffiti-cleaning company while the younger, ex-alcoholic Barry struggles to help with the business and paint pictures. The degree to which these young men's lives are compromised by emotional disturbance is soon demonstrated.

Steven, who at first appears a well-organised businessman, suffers an accident, cracks up along with his marriage to Maxine Peake's pregnant Debbie. The boys' mother, Ruth Sheen, brushes home truths under the carpet.

Barry, first heard talking childish nonsense becomes saner and more stable while Steven declines, hiding away in the cellar. It is there that Gavelle's painfully distraught Barry tells Steven what he already knows.

It sounds as if the boys' father may have been sexually abused by a schoolmaster, who in the fullness of time abused Barry, too, with Steven complicit in allowing the abuse to continue. It is further hinted the life of the boy's father may have been fatally disrupted by the teacher's illicit sexual activity.

The unexplained aspect of this grim, familiar narrative of sexual exploitation concerns Steven's complicity. Otherwise the well-acted play offers no illuminating insights into paedophilia.

Lisa Goldman's revolving-stage production, with dim lighting and ominous music, invests the play with impressive atmospherics it needs but does not deserve.

• Until 26 May. Information: 0870 429 6883.