As short as it is - 50 minutes - Caryl Churchill's latest work feels like two plays rolled into one. One is compelling. The other, not so.

Four middle-aged women sit in a sunny, suburban back garden chatting to each other about common acquaintances and the old times they've shared together.

In James MacDonald's vivid production, the brilliantly acted dialogue here is gripping in part because of its banality.

And then it is more gripping still as each woman reveals her own internal anxiety.

Sally (Deborah Findlay) has a paralysing phobia of cats; Vi (June Watson) did time for the manslaughter of her husband (though it may actually have been murder); Lena (Kika Markham) is agoraphobic; while our narrator, Mrs Jarrett (the utterly superb Linda Bassett), is outwardly delightful company while inwardly brimful of horror, the nature of which is revealed in her monologues that punctuate the garden tête-à-tête.

In these - or what I can only think of as the "other" play - she describes in detail an apocalyptic future and the suffering of the few survivors.

Churchill has been here before with such plays as Far Away. But there is something less convincing and more indulgent about the writing here.

It comes across as less of a prediction than an exercise in which the writer explores how far she can riff on her horrific visions before someone says: ''Now, come on Caryl, you're just being silly.''

Well, unfortunately it's down to me to say so. "Come on Caryl, now you're just being silly."