Guns and wit

The Riot Group deploys irony like a weapon of mass destruction, ripping with ease through the sentimentality and carefully constructed illusions inherent in political language. Last year, this furious and devastatingly funny theatre company reworked King Lear for a CNN-style newsroom, now they return as steely-souled marines, on a mission to assassinate a Middle Eastern dictator with a moustache and a country full of lookalikes.

Writer Adriano Shaplin punctuates savage observation with quasi-Shakespearean riffs on any subject from the idea of a war fought by babies (because they're cold-blooded and fearless) to the true value of the hot-dog. The cast's deadpan delivery, accompanied throughout by a shifting ambient beat, gives added punch to the desert-dry humour of such lines as: "If at first you don't succeed ... redefine success", or, "Victory forgives dishonesty".

Two benches run across an otherwise bare stage, for a production which shifts between the headquarters where the assassination is planned, and the scene of the assassination attempt.

Dressed in camouflage, the four members of the San Francisco company trade phrases, toying with concepts of poisoned diplomacy and bloodlust - whether it's Paul Schnabel's 51-year-old colonel grimly informing his pretty and flintily ambitious female lieutenant (Stephanie Viola) that he objects to "a world too weak to see you in a body bag", or Lieutenant Freud (Shaplin) asking: "Can you feel how much sense the world makes?" as he gets off on the excitement of having shot his ammunition.

Incredibly, Shaplin is only 24. If he and this brazenly intelligent group continue to evolve with such poise and originality (what other company could pull off a joke about Saddam's seductive eyes and the problems of infra-red goggles?) the theatre world will be a better if more cynical place. At the show's shocking end, the cast received a standing ovation from the front row - a fitting tribute to their lethal linguistic fireworks.

Until 25 August. Box office: 0131 556 6550.