Nothing but Sir Antony Sher's desire to portray the famous 19th-century actor and philanderer Edmund Kean can explain the decision to resuscitate Jean- Paul Sartre's grimly unamusing version of Alexandre Dumas's romantic melodrama.

In Adrian Noble's misjudged production the play is confusingly staged both in the 1950s, when Sartre's adaptation was premiered, and in Kean's own time - though in either period most actors, Sher excepted, adopt a burlesque style of heightened insincerity and affectation. No comic or satirical points are scored by this device.

In Sartre's updating Kean is less the glorious exponent of Romantic drama and more a wily sexual and social climber. True to Sartre's philosophy he does not quite know who he is: he cannot tell when he is being true to himself and, when acting, he and indeed the Prince of Wales slip drearily into Shakespearian role-playing.

Fresh emphasis is placed upon Kean's challenge as a lowly actor to rigid class divisions. Mark Thompson's setting encompasses both the Danish Ambassador's 1950s black-tie reception, where Joanne Pearce's arch, melodramatising Countess de Koefeld gazes at Edmund with premature rapture, and Kean's 19th-century dressing room, where he is caught in dreary situation comedy between the demands of the Countess, Jane Murphy's wooden, winsome ingénue actress and the interventions of Alex Avery's suavely convincing Prince of Wales. Unfortunately, Sartre's contemporary glosses do not brighten or modernise Dumas's torpid plotting.

Kean, that serial adulterer and Shakespearian tragic actor revered by Coleridge and Hazlitt, calls for an extrovert and dynamic actor endowed with charismatic, romantic charm. It calls in vain, for these characteristics have never been discovered within Sher's armoury of talents. Sir Antony is at his best when called upon to play threatening and sinister, fanatical and powerful.

Here, in unenergised and glum form, a dull voice either a throaty rasp or rising to mannered, high notes, Sher never conveys what a thrilling Shakespearian, seductive lover and exuberant character Kean must have been, or how different acting styles must have been then. It is an evening of unalloyed displeasure.

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