With the Byre theatre stripped of its production funding, and with the tiny Rapture Theatre receiving no more than a few pennies of public money, it was a smart move by both parties to pool their resources so that the Byre could continue to produce at least something.

This co-production of Pinter's Betrayal is the first result of the new partnership; a production of Michael Frayn's Democracy follows in the autumn. Let us hope they are on an upward curve because this first effort falls some way short of the mark.

It is not that the director Michael Emans has updated Pinter's script to the last ten years, instead of its original 1968-1977 time frame. Extramarital affairs are always with us, whether they are told chronologically, or, as here, from the end backwards. Pinter should know. Nor has the milieu of arty London changed that much. It would take a bit more to afford a whole flat for a lovenest at today's prices. But otherwise, the idea that a man would sleep with his best friend's wife seems all too contemporary.

So much so, in fact, that is rather harder to develop any sense of shock. That's not helped by Emans's failure to make anything of this new period. The main music, framing each half, is Leonard Cohen's Everybody Knows, a song released in 1988. And he uses the sounds of a typewriter to underscore the fact that these people are writers. But who uses a typewriter now?

On top of that, the drab set - or, to be more accurate, the loose arrangement of random bits of furniture - has no sense of style, let alone period. Rapture's shows are usually designed, as here, by Lyn McAndrew, Emans's partner on and off stage. They are often the weakest link in his productions.

As a consequence, the perfectly decent actors at the corners of the love-triangle, Paul Albertson, Clare Swinburne and David Tarkenter, have a lot to do to persuade one that this affair is anything that might matter to anyone not involved.

And here Emans's hands-off approach to directing, as testified by several actors who have worked with him, leaves them squarely in the lurch. Some scenes are reasonably effective; others are left swinging in the wind, with the performers struggling to make sense of the heavy freight of Pinter's dialogue.

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