Blood and Gifts, Lyttelton, NT, London

Blood and Gifts began life as one of the most praised of the short plays that comprised The Great Game, the Tricycle Theatre's ambitious 2009 cycle of works about Afghanistan. Its American author, JT Rogers, has expanded that 25-minute piece to a sharp-witted, if somewhat sprawling and repetitive, epic which is now unveiled in Howard Davies's lucid, adroitly marshalled two-and-three-quarter-hour production.

Spanning the 1980s, Blood and Gifts keeps track of the US's covert war against the Soviet occupation of Afghanistan. Our guide to the bewildering politics of the region is Jim Warnock, a CIA operative who is spearheading the counter-insurgency and tasked to liaise with the Pakistani secret service, through whom he is channelling aid to the anti-Soviet Afghan freedom-fighters. The question is which of the notoriously factious tribes will best serve the interests of the US, for whom this is a proxy conflict in the Cold War.

"They say tragedy is comedy, plus time. But Afghanistan? It is tragedy, plus time," declares Dmitri (Matthew Marsh), the wily Russian spy who, like Simon (Adam James), the shambolic yet often bull's-eye-hitting British MI6 agent, is one of Jim's regular sparring partners.

But Blood and Gifts works best when it offers a mordant, coolly satiric analysis of the motives, cultural miscalculations, and mutual suspicions of outsiders who regard this misbegotten, strategically vital country as merely a means to selfish ends.

There are some excruciatingly amusing episodes, such as the grisly Washington fundraiser where a right-wing senator treats guests to the spectacularly misguided notion that Afghans and Americans are "people of the book, joined as one!" and then extorts from the modest, aid-seeking tribal chief what turns out to be a media-friendly but wholly fraudulent sob-story. Rogers also has a good instinct for the comedy of mishearing and derives some humorous, non-patronising mileage (and one deeply affecting moment) from the Mujahideen's struggles to understand 1980s pop songs.

The production handles shifts of location smoothly. It's less successful, though, at disguising the lack of genuine emotional hinterland in the characters.

To 2 November (020 7452 3000)