HAS Webster’s grisly tragedy ever begun more oddly? Black-suited men and women sit in a tier of benches at the stage’s rear. And they politely watch and discreetly clap as Will Keen’s Duke Ferdinand wanders around with a mike talking to his followers and presenting a big silver cup to the upwardly-mobile steward who will soon secretly marry his sister, Charles Edwards’s genial Antonio. You might almost conclude that Calabria is Wimbledon, its prince a celebrity interviewer and the cast sponsors from a City corporation.

Add filmed faces on the plastic screen near the front of the stage and you have what is presumably a digital-era production of The Duchess of Malfi. I suppose the point is to suggest that a torrid old classic is not wholly irrelevant in 2003, but, if so, it seems unnecessary and even counterproductive.

Keen and Janet McTeer, playing Ferdinand and the Duchess whom he and his cardinal brother drive to destruction, manage to generate a Jacobean intensity. But a striped suit seems to inhibit Lorcan Cranitch as the other main character, the spy and assassin Bosola.

I have seen more menacing Ferdinands than Keen but few who were more unquiet. He fidgets, twitches, veers erratically from mood to mood. There is a built-in gulp in his voice which escalates into a crazy cackle or deranged gabble when he is roused. And what mainly rouses him, pretty clearly in this revival, is incestuous jealousy. After all, it is a none-too-usual brother who leaps on his sister in bed, french-kisses her and shoves a pistol first into her mouth, then into his own. Keen gets away not only with that but with such famously loopy cries as “I’ll go hunt the badger by owl-light”.

When he is in full lycanthropic flow, you understand why Shaw christened Webster “the Tussaud laureate”, meaning bard of the Chamber of Horrors. But, when you see McTeer develop the title-role, you realise he cannot be summed up so easily.

Here is a warm, generous woman who can happily marry beneath her, play merrily with her children, all without loss of dignity — and then, when disaster hits, make you feel that (as she says) she is “full of daggers”.

Daggers and worse. Her hair mattily straggling down onto an old cardie and dress, she sags, twists as she is surrounded by madmen is and forced to watch a film in which her loved ones are murdered, collapses, screeches in pain and finally finds a new dignity, but one that is now spiritual, not social. It is a luminous performance, and I only wish I could be as enthusiastic about some of those around her.

Could not Ray Stevenson’s Cardinal be more sinister and Cranitch’s Bosola less ordinary? Here’s a period malcontent torn between self-interest and decency, good and evil. But we never feel his melancholy, let alone his inner turbulence. Would this gentleman garotte the Duchess at all, let alone so unsweatily? As spies go, this normally fine actor is more cool Philby or bland Blunt than Jacobean killer. See what I mean by the illeffects of updating?

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