Sometimes art and life mirror each other in the most shattering ways: the murder of Joe Orton by his lover Kenneth Halliwell and Halliwell’s subsequent suicide, so much more shocking and grotesque than anything in Orton’s impish, savagely funny work, was a notable instance.

The mythology that accrues around such tragedies exerts a unsettling fascination. Watching a recent revival of Sarah Kane’s last play 4.48 Psychosis, it was impossible not to dwell on the writer’s fatal despair. And next month John Logan’s Red opens at the Donmar Warehouse about the artist Mark Rothko whose violent death was also self-inflicted. That will star Alfred Molina, who played Halliwell in Stephen Frears’s 1987 film Prick Up Your Ears.

As has been widely reported, Matt Lucas, who originally took the role of Kenneth in Simon Bent’s new stage account of the fraught Halliwell/Orton relationship, withdrew after his former partner Kevin McGee was found hanged.

Lucas’s replacement Con O’Neill, who joined Daniel Kramer’s production just over a week ago, faced a daunting task. Bent’s play, based on John Lahr’s biography and Orton’s celebrated diaries, tells an over-familiar but distressing tale in which Halliwell struggles with creative disappointment, envy, loneliness and depression, while the star of the working-class boy from Leicester, once his protégé, inexorably rises. It’s a demanding part to assume at short notice — particularly as here it is Halliwell, not Orton, who is centre stage.

Yet O’Neill delivers. His Halliwell is vain, prickly, obsessive, exasperating; he is also funny, intelligent, painfully self-aware and frighteningly fragile. Cradled in the arms of Chris New’s charismatic Orton — like an overgrown bald baby, bounding around him with puppyish glee or gazing at him with doglike devotion — his demand to be loved is moving and maddening. There’s a suggestion, even in his most buoyant moments, that O’Neill’s manic fooling about is a diversionary tactic, designed to prevent both himself and Orton from getting down to work, because he’s afraid that he will fail — and Orton won’t. His quiet triumphalism, when he tells their neighbour Mrs Corden (a compassionate, deliciously funny Gwen Taylor) how the tour of Orton’s Loot has bombed, is nastily convincing, his voice tremulous with delight, his lip curling with pleasure at the taste of blood. And as the awful, inevitable conclusion draws closer, O’Neill’s misery is drugged, numb — and cannot be borne. It’s a considered, detailed, poignant portrayal that lends Bent’s rather unsatisfying play a depth of affecting emotional realism.

To Nov 29. Box office: 0870 0606637

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