Theatre TAKING SIDES Criterion, London

Think about it. If Shostakovich had been German instead of Russian, if instead of The Sun Shines Bright Over Our Motherland he had written a cantata called Die Sonne scheint uber unserem Vaterland, would it be performed now? Almost certainly not. And if at the end of his life he had produced a book called Testimony in which he claimed that every time he had seemed to be praising the Nazi regime he had really been subverting it (as every true German would have understood), what would the world say? Probably something like "Pull the other one" - though perhaps a bit more strongly worded.

That uncomfortable comparison is touched on in Ronald Harwood's play Taking Sides. The German conductor Wilhelm Furtwangler, under investigation for possible pro-Nazi activities, wonders for a moment whether his American interrogator would be half so hard on Shostakovich, Prokofiev or Eisenstein ("especially Eisenstein"). The point is, surely, not to play off two monstrous regimes - Hitlerism and Stalinism - against each other, rather that most of us seem to have forgiven Prokofiev and Shostakovich for bending the knee to Stalin; they had to in order to survive.

Some would probably take that attitude now with Furtwangler, but there is still a core of resistance. No matter that he used his influence to save Jewish lives (quite a lot of Jewish lives, it seems), or that his decision to stay in Germany was almost certainly the result of a passionate (if somewhat naive) devotion to his country and his art. Praise for the artist still seems to demand some qualification about the human being.

Judging from his play, Harwood has few, if any such reservations. Eventually Furtwangler admits his naivety (followed by a gruelling physical breakdown), and we are allowed glimpses of the humane horror that partly motivates his interrogator, Major Steve Arnold (Michael Pennington).

But on the whole, Arnold is a monster, clearly based on the terrifying prosecutors at Hitler and Stalin's show-trials. Furtwangler is his scapegoat. Is that fair? Would a subtler, less hate-inspired line of questioning have produced something more thought-provoking, more ultimately valuable? The young American lieutenant (Christopher Simon) tries to look beyond crude moral types: a priest, he says, can be corrupt, deceitful, lecherous, "but he can still put God in the mouths of the people."

In itself, it's a strong image, but Taking Sides has actually given us little sight of real, solid corruption in Furtwangler. Major Arnold throws plenty of mud, but almost none of it sticks - except, perhaps, for the accusation of callousness in Furtwangler's treatment of the women his secretary allegedly "procured" for him. So the Nazis were able to use him as their No 1 cultural exhibit - that was part of the price he had to pay as he walked his political "tightrope". Harwood's Furtwangler is seen as artistically determined to preserve that which he believes in, and politically engaged in a very laudable form of damage-limitation. So he wasn't prepared to go to the gallows: would you be?

In the end, though, what really exalts Furtwangler is Daniel Massey's performance. He not only looks and sounds the part, his every move is reminiscent of the Furtwangler one can see in films - the arm-movements flailing but hugely eloquent. He is vulnerable, sensitive, tormented, but also immensely dignified. How can one not believe him?

The historical accuracy may be hard to gauge. But however much we may enjoy demythologising heroic figures today, can we really do without them? Without examples of goodness under appalling pressure, it's all too easy to despair in the face of evil. If Furtwangler was fallible, even "cowardly", that makes his heroism less impossible, less remote and thus more inspiring - just as in the case of Shostakovich. If that is the play's message, it is very timely.

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