When it first played on Broadway in 1976, Stephen Sondheim's musical about the collision of American imperialism with Japanese isolationism fare poorly. Did Hal Prince's big-scale production swamp a thoughtful little show?

Gary Griffin's revival, first staged at the Chicago Shakespeare Theater, favours intimacy over spectacle. A versatile cast of ten act in the round. There are just four musicians. Every syllable registers in this bare setting. But the lack of showbiz camouflage also exposes how little Sondheim and John Weidman's story has to grab us with.

Historical context? They got it - in fact, they've got little else. The Japanese sing about their agrarian lives, then - at length - about the arrival of warships in "Four Black Dragons". Conflict ho, you think, as an expository first hour drags to its end. Instead we get a song about how nobody knows what went on in Admiral Matthew Perry's 1853 meeting with the emperor. It's a rotten anti-climax.

The best song, "Chrysanthemum Tea", addresses this frustrating placidity, as the Shogun's advisers take toxic action against his shilly-shallying. It's sung superbly by a cast that offers enough energy and wit to make you wish they were playing characters you were asked to give a damn about.

There are lovely touches, of course, loads of intelligence at play. A Sondheim turkey is still a bird worth nibbling at. But Griffin's decision to use a small cast who jump between Eastern and Western muddies what little sense of character there is. Without a stronger sense of what's at stake for the individuals - or sparkier tunes, for that matter - this rebuke to imperialism makes for a pretty dry night out.