Tim Fountain’s fascinating, apparently true-life play views the dilemma of being gay in 1950s Hollywood from the differing perspectives of Roy Fitzgerald, a hick young man who aspires to be a film star, and Henry Willson, a famous agent, who triumphantly subjects him to a Pygmalion-like process of change.

Tamara Harvey’s sensitively nuanced production, enhanced by a sombre Edward Hopperish office and Hockneyish pop art view of Hollywood designed by Morgan Large, creates just the right mood.

When young Roy, played by Michael Xavier, appears in Willson’s office, he seems about as much male sex-symbol material as Kenneth Williams. He is high-voiced, physically awkward and tentative. Yet Willson, the maestro of abrasive, outspoken cynicism in the charismatic, comic performance of Bette Bourne sees movie potential in his looks and physique.

The business of converting Roy Fitzgerald into Rock Hudson, of making the cissie-boy butch, is accomplished in over-compressed scenes of high comedy. Xavier, a real theatrical discovery, charts the masculinisation procedure with convincing assurance. The impassive Willson, to whom Bourne lends the perfect air of closeted misanthropy, revels in showing Rock how to walk tall and speak with low-voiced confidence. Thanks to Willson’s publicising flair, Rock is quickly launched upon his career as a star, though it is not long before he consents to marriage to stem the tide of malign whispers.

Fountain conveys a vivid impression of the witch-hunting, McCarthyite times, with gay male stars under surveillance. Yet he needs to probe deeper and explain more about the impact of 1950s homophobia on the two men and their private lives. There are psychological, sexual and political matters left unexplored in this evocation of a Hollywood that 50 years on still keeps gay stars in closets.

Until June 21 (020 7582 7680).