Secret Theatre Show 6 (Edinburgh Fringe)

Mark Ravenhill's new play for the Secret Theatre company – though it only involves three of the ten-strong ensemble – was inspired by a passage Ravenhill read about orphaned children of victims of the Pinochet regime who were subsequently adopted by their oppressors.

It's an intriguing premise, involving the search for identity in a moral vacuum of wealth and power, but the result fails to pack an emotional punch.

Steven Webb plays a young man haunted by the words of a "chav" he and a friend (Cara Hogan) encounter in a favela, telling him his parents are not his own. That would explain why, among other things, the woman he believes to be his mother (Matti Houghton) flirts so outrageously with him in her white bathing costume.

Further investigation reveals that his real mother and father were both political opponents of the current regime during a long-distant coup, a fact his Oedipal stepmother is quick to deny.

Despite some early promise the narrative soon becomes frustrating, not helped by the fact the majority of dialogue comprises fragmented, half-spoken sentences. The milieu of drug-taking, bribery and murder creates the heady atmosphere of a South American cartel, though the cast seem an odd fit in this context.

It's neatly and efficiently staged by director Caroline Steinbeis in Paines Plough's excellent portable Roundabout venue tucked in behind Summerhall. But I'd suggest that if you want to see the Secret Theatre ensemble at its best you head to King's Hall for A Series of Increasingly Impossible Acts.

Show 6 runs at Summerhall until 17 August

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