Time and a world-tour have been unkind to Trevor Nunn's Royal Shakespeare Company production of The Seagull that I admired at Stratford-upon-Avon. It alights in town all torpid and lethargic, looking distinctly blue and bird-fluish.

It takes three hours and 20 minutes of hard theatrical labour to bring Chekhov's study of unrequited lovers in the world of the idle, modestly-landed gentry to its suicidal finale. Nunn's production is hampered by monotonous langour, conceptual vagueness and melodramatic pointing, such as the vulgar interpolation of Konstantin's suicide attempt.

Christopher Oram's setting mysteriously combines realism and expressionism. It retains the designs for Nunn's King Lear, with that crumbling edifice of a theatre balcony visible. A few birch trees and pieces of furniture are scattered around, with a vague lakeside rear view, as if to suggest The Seagull highlights the dilemma of people for whom life is all theatrical performance.

Gerald Kyd's handsome, bearded Trigorin, who ought to transmit sexual electricity, rises to the challenge of Romola Garai's smitten Nina and succumbs to Arkadina's erotic appeals with all the vigour of a sedated tortoise.

Richard Goulding plays Konstantin on a note of tremulous self-pity.

At Stratford this Seagull was far more bathed in the shades of romantic melancholia - and distinguished by the illuminating, psychological insights of Miss Garai's performance. Shrill, ardent, gawkily demonstrative with her long hands, her still superlative Nina regards Konstantin, who welcomes the girl with puppy-like excitement, as the means to launch her acting career.

She falls for Trigorin with the fanaticism of an obsessive hero-worshipper. She returns to Konstantin after her affair with the novelist, shattered by love, her high voice cracking in the throes of a nervous breakdown. Miss Garai remains this Seagull's chief glory.

Monica Dolan's alcoholic, despairing-Masha and Melanie Jessop, jealously pining for Dr Dorn, beautifully complete the gallery of rejected lovers. And William Gaunt's decrepit Sorin (he alternates with Ian McKellen in the role) exudes a fine, comic dejection.

Frances Barber, who at Stratford burlesqued Arkadina as a Russian equivalent of a Billingsgate fishwife, turns in a dramatically improved, impressive performance. All the farcical flouncing has gone. Her selfish, superannuated actress basks in self-admiration, as if to conceal sexual insecurity. She aspires to be maternal with Konstantin, while heart and ego are otherwise engaged.

Such performances hit home. But, oh, this Seagull's slow-flapping, night flight.

• Until 12 January (0870 890 0141).