In any other city in the world, the discovery of Mary-Jane Palmer's body floating in the river would have been sad, and disquieting, that was all. A four-line filler on the inside pages of the daily newspapers. A minor tragedy passed over like a dead bird in the road. But this was Paris, the river was the Seine, and because of that the proceedings were tinted with a vague gothic suggestion of romance. A small crowd gathered - middle-aged businessmen...