This two-hand murder-mystery differs from the great many other comedies we've seen recently where a small cast of actors dash about playing a large number of characters in a couple of important respects: it isn't based on an existing out-of-copyright novel, and it's a musical. Originally performed fifteen years ago in Chicago, director Caroline Leslie has added an extra British layer, which apparently came from designer Jess Curtis, to set it in a 1950s BBC radio studio.