Pornography, Tricycle, London

Simon Stephens's play ripples with tension. The title refers to how we might view things, not what they are. We are awaiting the bomb blasts on the Tube trains and buses four years ago and eavesdropping on the lives of those affected, while a terrorist makes his way to King's Cross in July 2005.

The play, co-produced by the Birmingham Repertory Theatre, was commissioned and produced by a theatre in Hamburg and seen at the Traverse in Edinburgh during last year's festival. It captures the randomness of the horror by showing a cross section of ordinary lives bumbling towards it, and the Olympic Games beyond in 2012.

Sean Holmes's production is a brilliant exercise in Brechtian alienation. Inflamed monologues merge with isolated sound bites. The designer Paul Wills has turned the stage into an extension of a Tube train, lights hanging in neon strips, the participatory sound engineer evoking Coldplay's "Yellow" as an alternative national anthem.

There's a schoolboy whose problems include having the hots for his teacher. There's the grown- up female pupil who is drawn back to her male professor (I sensed Stephens trying to re-write David Mamet's Oleanna while sculpting his text; that's another play). There's the old widowed biddy with strong views – beautifully evoked by Sheila Reid – and, at the heart of the play, the inquisitive, blooming, incestuous relationship of a brother and sister, played by Sam Spruell and Kirsty Bushell.

The most powerful moment of the play is Bushell's emotive outburst when her brother, whom she has exposed as a sexual lifeline and thought was dead, walks in. She'd been waiting for him to call her as London sleepwalked through disaster. Spruell is bravely naked and eloquent in his role as the brother.

Stephens counterpoints these snapshots with the slow, poetically appreciative progress of a bomber through a countryside he loves. It's not a question of sympathy for the devil; it's a notion of satirically challenging his motives for the destruction.

Anthony Welsh plays this avenger with light empathy, while Sarah Solemani and Sam Graham as the academic couple, and Frances Ashman and the remarkable Billy Seymour as the teacher and pupil, are superbly articulated versions of souls at sea in a cruel world that is about to become even more so.

It's a brilliant piece; strange, hypnotic, and unsettling.