Orphans, Traverse Theatre, Edinburgh

What does it take to bring a world crashing down? In the case of Helen and Danny, a married couple with a new-build and a young son, crisis comes in the shape of Helen's brother, Liam, who shows up in their home one evening, drenched in another man's blood.

This is the gripping premise for Orphans, Dennis Kelly's taut and unsettling new play, which continues the Traverse's excellent run of new-writing form this Fringe.

Helen (Claire-Louise Cordwell) and Liam (Joe Armstrong) are siblings bound by the trauma of losing their parents who "were burnt to a crisp in a fire" when they were kids. Helen and Danny (Jonathan McGuinness) are a mainly happy couple whose relationship is showing its first cracks as they decide whether to have a second child.

Over the course of an enervating two hours (slightly too long; it could easily lose 15 minutes and get rid of the tension-deflating interval), the trio haltingly reveal what has happened to Liam in a narrative of escalating menace and horror that would make Pinter squirm.

This is a very bleak look at modern life – a world of miscommunication and mistrust where feral youths and violence reign on the streets. Which is not to say that there aren't also some moments of jet-black humour in Kelly's script. His stop-start dialogue, where no-one ever quite says what they mean, means what they say or finishes a sentence, is delivered most powerfully by Cordwell's ballsy Helen: the compelling lynchpin of the unholy trinity. This creepy tale builds an atmosphere that lingers long after the curtain call.

To 30 August, not 17, 24 (0131-228 1404)