Inspector Morse isn't sure what to make of the truncated body found dumped in the Oxford Canal, but he suspects it may be all that's left of an elderly Oxford don last seen boarding the London train several days before. Whatever the truth, the inspector knows it won't be simple -- it never is. As he retraces Professor Browne-Smith's route through a London netherworld of topless bars and fancy bordellos, his forebodings are fulfilled. The evidence mounts; so do the bodies. So Morse downs another pint, unleashes his pit bull instincts, and solves a mystery that defies all logic.