Like a Fishbone, Bush Theatre, London

I had high hopes for Like a Fishbone, the new play by Anthony Weigh. His previous piece at the Bush, 2,000 Feet Away, was a sharp, thoughtfully balanced look at how a society's over-reaction to paedophilia can be strikingly counter-productive. So it's particularly dismaying to find him trading now in his own brand of melodramatic extremities in this latest work, which arranges a heated but enlightening scrap between religious faith and rational humanism.

In the aftermath of a Dunblane-like massacre at a remote, rural school, an architect is hired to design a memorial. On the evening that she is to give a presentation of the model, this woman is visited by the mother of one of the victims who deeply disapproves of the plans. The trouble is that, in order to maximise the psychological tension, Weigh creates a couple of clichéd, matching fanatics as adversaries.

Spouting corporate-speak, Deborah Findlay's soignée architect wants to memorialise the lack of spiritual meaning in the senseless atrocity by preserving the school just as it was at the time of the mad gunman's attack. In a twist worthy of a B-movie, Sarah Smart's young mother is unsighted (blind faith, get it?), and spurred on by her dead daughter, she wants the school razed to the ground and a religious symbol erected in its place. "I will always choose God over the truth," she cries.

Josie Rourke's production is well-acted and, with rain streaming in the dark outside the windows of the audience-embracing room, it skilfully intensifies the play's somewhat contrived thriller-like claustrophobia. But I'm afraid that I did not believe a word of it, especially when the pair's contrasting failures as mothers were crudely related to their opposed creeds. Phoebe Waller-Bridge is amusing as a posh, eager intern who injects a note of welcome sanity. In general, though, this disappointing drama feels like an exercise in the Higher Hokum.

To 10 July (020 8743 5050)