Bent, Trafalgar Studios, Rock'n'Roll, Duke Of York's, London

Still packing a terrible punch

I knew that Bent would be an emotionally gruelling play, but I hadn't expected it to be so deeply upsetting - for reasons that are both to the credit and discredit of the piece.

Somehow, I had managed to miss seeing, until now, any production of Martin Sherman's iconic 1979 drama about the fate of homosexuals in Nazi Germany. So my introduction to it is this high-profile revival by Daniel Kramer, starring Alan Cumming, and which, as a piece of stagecraft, I found at once highly accomplished and, given the subject matter, a little too confident in its deployment of "theatrical effect".

The play opens with perhaps the most disastrously unfortunate sexual pick-up in modern drama - inopportune, too, for it's the Night of the Long Knives, when Hitler liquidated Ernst Röhm and all his gay storm troopers. From now on, in Germany, it would be suicidal to be openly gay. Sherman's protagonist is a man whom, initially, it is not easy to like and, to my mind, the remarkable Cumming makes him too audience-friendly from the start.

Max is a drug-dealing, apolitical, sexual violence-loving tart. Sherman endows him with a drive for survival that overrides all other considerations. The most shocking scene is set on the train to Dachau. The Nazis invite Max to deny his sexuality, and save his skin, by disowning his dancer friend Rudy (Kevin Trainor). Given a truncheon, he clubs the half-dead boy to extinction in a delirium of anguish and self-protection.

You want the character to understand that life is not worth living if, to prolong it, you have to betray the very reason for being. Bent takes Max on a journey that finally makes him appreciate that.

The most famous scenes in the play dramatise the love that grows between Max and Horst (sensitively played by Chris New), the gay ex-nurse he first met on the train. At the camp, where the two of them are given the demoralising and deliberately futile task of humping stones, homosexuality is considered an even worse crime than being Jewish. So the circumspect Max contrives to be classified as a yellow-starred Jew rather than as a pink-triangled gay. Horst dislikes this intensely, yet he and Max develop a closeness that surmounts the barriers the Nazis place between them. At one point, though they are not allowed to touch or look, they bring one another to orgasm through the power of words alone.

It's in the scenes in the camp that the play signals its (honourable) late-Seventies origins. A colleague, as he left the theatre, grouched that the piece boils down to, "Be out, and be proud". To which the response is: and why shouldn't it? None the less, there is something troubling. The play goes out of its way to record that homosexuals do not have a monopoly of virtue, and come in many types. But in order to make its point with maximum clarity, the play resorts to simplification. It's significant that no authentically Jewish inmate appears on stage, and the piece doesn't guard enough against leaving the impression that there is a pecking order among the ranks of the reviled and persecuted. Its engagement with identity-politics is very understandable, but you might easily forget that the human race is a family and that there was a family against fascism.

Communism is the "perversion" at issue in Tom Stoppard's great play Rock'n'Roll, which continues its triumphant run with one major cast change. The excellent David Calder is much better casting as the militantly unrepentant Marxist professor. He is superb at bringing out the intellectual bully and the needy, overgrown baby.

Trevor Nunn's production is now firing on every cylinder, and if Rufus Sewell and Sinéad Cusack don't walk off with all of this year's Best Actor awards, there is no justice.

'Bent' (08700 606 632), to 13 January 2007; 'Rock'n'Roll' (08700 606 623), to 5 November