When Terence Rattigan's closet lover, the actor Kenneth Morgan, killed himself after one of their frequent break-ups, the sad incident became the inspiration for the playwright's 1952 masterpiece The Deep Blue Sea.

Of course, given that both suicide and homosexuality were still considered high crimes in post-war Britain, a few key changes to the story were necessary if the play was ever to get into production, let alone pass muster with the Lord Chamberlain. And so the middle-aged protagonist, obsessed by a younger man's flesh and tormented by an unrequited passion, became a woman, Hester Collyer.

In Thea Sharrock's elegant new production, conscientiously set in period, this sexually charged anti-heroine is played by Harriet Walter, who delivers a performance of such power, that even those who dislike Rattigan's usual witty, middle class boulevardier style, cannot help but be moved to tears.

Walter's Hester leaves a life of affluence and an eminent High Court judge husband for a shabby flat and socially downgrading affair with a former Battle of Britain pilot cast adrift into Civvy Street. At the start of The Deep Blue Sea, she attempts suicide, believing her love is not reciprocated. The rest of the play is concerned with Hester's personal journey from rock bottom to an uplifting self-confrontation and a possible future, albeit an uncertain one.

Set in Rachel Blues' handsomely designed west London flat, exquisitely lit by Chris Davey, the entire production is a real class act - and a terrifically cast one at that. Robert Portal's character, Freddie Page, was described in the original production as "shiftily charismatic, a jauntily sexy figure, a born lady killer". Portal convinces in all respects: a troubled, disillusioned and immature former war hero, who is careless in his feelings towards Hester but nonetheless loves her in his own way. He matches Walter scene for scene, the two of them generating a constant undercurrent of passion and lust, without any overt sexual references.

Neil Stacy does what he can with the rather unrewarding role of Hester's tight-buttoned but constant husband while Una Stubbs brings some welcome comic relief as landlady Mrs Elton, a part which betrays the class-consciousness of the era in which Rattigan was writing. And Roger Lloyd Pack, as the mysterious ex-doctor who provides the catalyst for Hester's reinvention of herself, delivers a mesmeric performance of spooky understatement.

At its premiere, some critics quibbled with the play's comparatively upbeat ending, and yet The Deep Blue Sea remains a beautifully constructed piece whose immense capacity to move is well proven in this production with Walter's outstanding performance at its wounded heart.

- Stephen Gilchrist (reviewed at Richmond Theatre)