A play with this title has an obvious resonance right now. But the extraordinary thing about this deft and brilliant piece by Siberia's Presnyakov Brothers is the way it extends the definition of “terrorism” to embrace most of modern Russian life. Structurally, the play is rather like a violent version of La Ronde; tonally, its mood of dazzling apocalyptic farce suggests the novels of Kurt Vonnegut or Joseph Heller.

The action starts, in Hildegard Bechtler's ingenious design, with a simulated airport bomb-scare, to which the Theatre Upstairs audience becomes a helpless witness. And although the next scene, involving sadistically adulterous love-play with a woman shackled to a bedpost, initially seems like a sudden jump-cut, we soon work out the hidden connection. In fact, each of the play's six scenes, including an office-suicide and infighting amongst the city's military police, appears to be a discrete demonstration of terrorism: the artfulness lies in the incremental portrait of a world in which abnormality has become the norm.

What is startling, however, is the surreal humour that these two brothers bring to their task. You see this at its wildest in the third scene, where it is discovered that an office-worker has hanged herself in the relaxation room: an event that is treated more as an irritant than a tragedy, especially by the resident psychologist who can't get at the dog leash he desperately needs. Even the shocking revelation, in a later scene, that the bomb-disposal police are voyeuristic accident-perverts is capped by the bizzare detail of their boss crooning Happy Birthday, Mr President in the style of Marilyn Monroe.

This is a play about the breakdown of society in contemporary Russia. What astonishes is the cool, sardonic wit that the Presnyakov brothers bring to their task. And this is beautifully realised both in Sasha Dugdale's translation and in Ramin Gray's poker-faced production. Instead of treating the characters as Gogolian grotesques, Gray assumes that violence is now an everyday fact of Russian life.

Thus in one scene Di Botcher and Sheila Reid play two old biddies sitting on a playground bench; and the casualness with which the former passes the latter some poison-tablets to despatch her son-in-law speaks volumes. Even in the bedroom scene there is something disturbingly nonchalant about the way Paul Hilton transforms the erotic games he is playing with Suzan Sylvester's trussed-up victim into dangerous reality. And Alan Williams as both the dog-petting psychologist and the singing military policeman makes the absurd seem hilariously plausible. Russian society may be in disarray, but, on the evidence of this and the recent work of Vassily Sigarev, a sense of dislocation yields first-rate drama.

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