As that magnificently smitten couple, Antony and Cleopatra, who put ecstasy before empire, Patrick Stewart and Harriet Walter made a big, memorable impression last April at Stratford-upon-Avon's Swan Theatre.

Transferred to the larger, traditional Novello stage Gregory Doran's production has sadly lost much of its originality, its intimate focus and forcefulness. At Stratford Stewart's remarkable Antony, an almost bare-chested general, disturbed by the last, hot flush of middle-age, succumbed to self-disgust and melancholia as he exchanged political power for Cleopatra's body and soul.

Walter, a brisk, handsome and imperious headmistress of a girls' public school rather than a vocational voluptuary, still achieved something refreshing and valuable. Her Egyptian queen interestingly lacked sexual confidence - her Sixties Biba wig was and is a sign of it. She betrayed vulnerability, a constant anxiety about her ability to keep Antony enthralled. It was this Cleopatra's weakness, not her strength, that riveted attention.

For London, though, the complexities and subtleties of the couple's relationship have been ironed out. The outstanding characteristic of Stewart's Antony is now his bellowing fury in the face of military and political defeat. The general's melancholia and self-hatred have been shaded out. So too has the self-loathing. Stewart's Antony still capers, gambols and dances like a lost youth with this elegant but vocally monotonous Cleopatra, who now shows more steel than nervy lack of sexual confidence. Their relationship remains larky, sparky but is no longer overwhelming.

Doran's production also cries out for scenic invention and development for the big Novello stage. Stephen Brimson Lewis's design remains minimal, with just a map of the old Roman Empire imprinted on a glass panel, rear stage. It serves as a decorative rather than dramatic emblem. There is no serious attempt to distinguish between the dour Roman world and its sensual Egyptian counterpart. An upper gallery is called just once into action, when it becomes the monument, up to which the dying Antony is hauled as if he were some stricken horse. Cleopatra's lament for his death and the arrangements she makes for her own suicide, with Julian Bleach's spooky clown in charge of the asp, left me unusually dry-eyed and unmoved. For Walter, despite that familiar vocal quaver of hers, sounds heroically self-possessed as she takes the snake to her broken heart and gives the world a cool goodbye.

This Antony and Cleopatra has, however, improved dramatically where it deals with imperial politics and warfare. John Hopkins's superb Octavius, a master politician who is powered by seething neurosis and anxiety, creates an ominous atmosphere of distrust and suspicion wherever he appears. Hopkins lets you see that it is Octavius's disgusted puritanism that powers his attack upon Antony. Ariyon Bakare's Pompey leads a swaggering troop of sailors in a scene of drunken male carousing that reveals Stewart's Antony happily escaping from sex's bondage. Ken Bones makes a wonderful, craggy skullcapped Enobarbus. He observes the canoodlings of Antony and his misfortunes of war with a fine, wry cynicism.

Doran, by creating stage pictures in which characters stand in line speaking out at us, too often gives scenes a stilted, statuesque appearance. Yet the battles that burst out as the triumvirate falls apart are magnificently managed in an expressionistic haze of smoke, darkness and Adrian Lee's evocative music. Ironically this Antony and Cleopatra succeeds best with military rather than sexual warfare.