This remarkable 90-minute monologue was John McGrath's final work for the theatre before his untimely death. The first part is a cogent attack on the power of the multinationals, the second, written after September 11, links suicide bombers with anti-globalisation protesters. Even if the connection seems slightly strained, McGrath argues his case passionately and is driven by a fear of the planet being turned into a battleground "between the clever rich and the desperate poor".
His speaker is a humane middle-aged MI5 operative. Having worked on the Iran and Afghanistan desks, she is now required to infiltrate the people protesting against global capitalism - or else retire to a life of begonia-growing and TV-watching. McGrath carefully charts her increasing sympathy for the people she is required to spy on, and her growing belief that it is the big corporations that demand penetration.
McGrath writes throughout with a controlled anger and a belief in the validity of personal protest, and his piece is given a beautifully shaded performance by his widow Elizabeth MacLennan. Directed by McGrath's daughter, Kate, this is that relatively rare item, a necessary piece of theatre.
· Until August 26. Box office: 0131-556 6550. Then at the Tricycle Theatre, London NW6 (020-7328 1000), from September 5-14.
