Verbatim theatre is apparently the new journalism, but there are times during Guantanamo - about the detainment without trial of suspected terrorists in Belmarsh prison in London and in American camps in Afghanistan - when you start longing for a little old-fashioned drama.
The relentless rise of verbatim theatre over the past couple of years has once again put theatre centre stage. Theatre now matters because it is about things that matter. Only a fool would choose Jailhouse Rock over Guantanamo. But Guantanamo over Democracy? That's trickier: the fictional take on facts in Michael Frayn's play permits the exploration of grey areas, while the journalistic style of Guantanamo offers only black and white.
For all its well-meaning and heartfelt power, Guantanamo strikes me as part of another genre that is increasingly taking over our stages: indignant theatre. Whether its subject is the botched privatisation of the railways or the legal black hole that allows hundreds to languish in prisons without hope of freedom, it puts on stage what once might have been popped on a postcard from "Disgusted of Tunbridge Wells". Except that in this instance the disgust comes from the liberal-minded and talks to the liberal-minded. For most of its audience it will only confirm not challenge.
Does that matter? Not particularly, although if you really want to change the world, the TV documentary would be more effective; the newspaper article would require tighter arguments and a more stringent examination of the evidence than is offered in this mixture of interviews with families and lawyers and excerpts from political speeches. At its best Guantanamo questions the nature of democracy itself and, of course, I am delighted that it is playing in the West End. I just wish it wasn't playing so much to the gallery.
· Until September 4. Box office: 0870 060 6627.
