It's very odd, when you think about it: a theatre which has scarcely staged straight drama for years was packed out on the opening night of a first play by an unknown writer.

The explanation, of course, lay in the casting of TV comedian Dawn French and singer Alison Moyet in two of the three roles. You could argue that Carmel Morgan, a member of the Coronation Street writing team, has written not so much a play as a vehicle for two improbably-teamed stars.

So you have a structure where in the first act Moyet's contribution consists almost entirely of singing. The idea is that Bernice (French), a teacher, is the daughter stuck at home looking after a disabled mother (June Watson) while her sister Cath (Moyet) is pursuing a low-key singing career in Spanish clubs. The main action takes place in the family home, with interspersed episodes of Cath singing in her club.

It is only in the second act that Cath returns home and recriminations between the sisters turn into a direct confrontation.

So the bulk of the play is about Bernice and her relationship with her mother. In between lifting her on and off the toilet, Bernice is driven to distraction by her mother's obsession with goings-on in the road.

This suffocating relationship recalls Martin McDonagh's The Beauty Queen of Lenane, and, as in that play, Morgan hints that the trapped daughter is as likely to slip into her mother's chair as to take flight when the burden is finally lifted. But any further comparison only highlights the difference between a competent soap writer and a theatre writer of genius.

Still, as a vehicle it evidently serves its purpose. With Dawn French in familiar Vicar of Dibley comic mode and Alison Moyet ill-at-ease wth the acting but sweet-voiced in some not very memorable songs, the audience seemed delighted with it. The biggest scream of shocked delight, though, was reserved for Bernice's mother calling her a "fat f****r ". It's that sort of evening.

* Running time: Two hours 15 minutes. Until Saturday.

Terry Grimley