What shock appeal Caryl Churchill's latest flight into theatrical fantasy generates! Two male lovers - one prepared to leave his wife and children for his new, special relationship - sit on a sofa, talking of foreign affairs as America has violently practised them from Vietnam to today.

They go no further than gazing into each other's eyes, a little mutual knee touching and, once, one rests his head in the other's lap. This, though, is a politically motivated allegory, a theatrical depth charge, a tirade against the thrust of America's foreign policy and Tony Blair's obsequious support of George Bush in Iraq.

Inspired by cartoonists, stand-up comedians and commentators who have likened Blair's relationship with Bush to a love affair, Churchill takes an imaginative leap into allegorical fantasy. In Drunk Enough To Say I Love You?, Stephen Dillane impressively plays diffident, charming Jack, as in Union Jack, who becomes sexually captivated by Ty Burrell's riveting, hunky, fearful Sam, as in America's Uncle Sam, who is half in love with torture too.

Jack voices his support for a host of our allies' interventions abroad and reveals himself bound, ideologically not literally, in a sado-masochistic relationship-with his lover. He echoes his Master's Voice on America's decades long programme of dirty tricks abroad - the black propaganda, policy changes over Afghanistan and Saddam Hussein, not to mention gases, poisons, torture programmes and bombs assisting these ventures.

He vainly tries to escapes his lover's domination, going home after daring to disagree on Israel, but abjectly returns to offer "the total commitment" demanded of him. When, however, Jack challenges Sam's laissez-faire policy over global warming and the American is left vainly chanting "love me, you have to love me", the spell is broken.

Churchill makes this relationship of control and submission serve as a scathing analogy and critique of Blair's attitude to America. The black comedy might, however, have seemed a monotonously one-sided tirade, had not Churchill written it in fascinatingly strange, elliptic speech, fragmentary, incomplete phrases of telegraphese. You need listen closely to understand.

In James MacDonald's beautifully composed and acted production, the sofa on which the men sit, is suspended in the air, as if suggesting - not only when Sam feeds Jack cocaine - that the men float high above reality's hold. An astonishing piece of theatre.

• Closes 22 December. Information 020 7565 5000.