Muswell Hill's husband-and-wife team Maureen Lipman and Jack Rosenthal are rumoured to be under investigation by the Monopolies and Mergers Commission for cornering the market in Jewish humour. Actually, there is serious competition from Radio Four. On Desert Island Discs recently, Rabbi Hugo Gryn told a glorious Jewish joke which even got a laugh out of the relentlessly demure Sue Lawley, and Lionel Blue has an audience of millions.

Yet our Jewish playwrights - Rosenthal the honourable exception - tend not to write 'Jewish comedy in the way that Americans do. Harold Pinter and Arnold Wesker aren't big on guilt-laden, self-deprecating laugh-fests in the manner of Neil Simon, Woody Allen and now Wendy Wasserstein. Her latest hit, The Sisters Rosensweig is set in London and is currently previewing to enthusiastic audiences.

'I had a hunch that this was a good one, and I was right. They just love it. I think this play could tour the world.' Alongside Lynda Bellingham, Maureen Lipman and Janet Suzman, Larry Lamb (below) is playing Merv, the New York fake-fur furrier. 'I don't know my origins, but in my Spanish/Portuguese background there's some Jew in there. It's rather a pleasure to be playing one and discovering bits of myself. Her observation is just wonderful. It's a real case of NAR.' NAR? 'No Acting Required. It's all there. Just say it.' It would appear that he's right.

'The Sisters Rosensweig' is previewing at Greenwich Theatre ( 081-858 7755)

(Photograph omitted)