Chiwetel Ejiofor achieves something extraordinary and historic in Michael Grandage's misty, crepuscular vision of Othello and devilish, sexual mischief in Cyprus.

Ejiofor has recreated Shakespeare's Moor of Venice, refusing to play him along traditional lines as either victimised tragic hero, stupid, self-dramatising egotist or even a combination of these opposed character facets.

Instead he offers a riveting, psychological diagnosis of Othello as a black African outsider in a white world, whose sexual and social insecurities make him masochistically susceptible to the sadistic manipulations of Ewan McGregor's Mr Monochrome - an Iago with a personality by-pass, but dangerous nonetheless.

An anachronistic case of sadomasochism in Shakespeare then? Oh yes, absolutely! Seen in this light Othello travels eagerly on the road to self-destruction and to the murder of Kelly Reilly's pathetically vulnerable, devastating-Desdemona, a girl as fragile as a candle in the wind. Never before has the killing looked as psychopathically brutal, with the woken wife dragged from bed and strangled centre-stage before Michelle Fairley's fine, down-toearth Emilia erupts upon the scene.

Ejiofor's bearded, African-sounding, very Christian Moor, whose charismatic eyes dominate the stage, never basks in the military self-importance of conventional Othellos.

He lacks swagger and confidence: odd then that Grandage omits the epileptic fit which the Moor is supposed to suffer. When, though, the seeds of suspicion have been planted in Othello's mind by Iago, Ejiofor allows them to flower in that grand farewell to the Moor's greatness. Then as if rebelling against the swirls and eddies of Othello's language, Ejiofor turns eerily quiet.

He demands evidence of Desdemona's non-existent passion for Tom Hiddleston's handsome, come-hitherish Cassio, with the fervour of a man determined to strap himself upon the rack of suffering. Ejiofor has difficulty weeping - and Othello is famously tearful - but how well he anguishes, luxuriating in his pain right down to what becomes a gloriously howled finale of satisfied masochism. "Whip me ... blow me about in winds, roast me in sulphur."

If only he waved his hands less. McGregor's Iago performs a curiously insipid role in this S & M dance of death. With the air of an aloof butler planning steps to his master's downfall he neither convinces as brilliant deceiver nor as a depraved manipulator. He has none of the ingratiating deference or chilling inscrutability of Ian McKellen's definitive Iago or of Antony Sher's ostentatiously evil Ensign. He even scorns the notion, persuasively advocated in the programme, that Iago is homoerotically driven or contaminated by envy and racial hatred.

Grandage fields an uncharacteristically bland, under-developed production, which designer Christopher Oram locates first in a Venice notable for church bells, a black/gold backcloth and a watery gutter, then in a murky Cyprus of cicadas and thunder, set against a crumbling wall. Light shines through a single, grille door. There is no acute atmospheric definition, no strong sense of the difference between Venice and Cyprus that marked Sam Mendes's famous film noir production at the National.

It is Ejiofor who makes this such an illuminating and revelatory Othello.