Clever, clever, and more clever! I would never have guessed the killer's identity if I hadn't already seen the 1940's movie before reading this. HowevClever, clever, and more clever! I would never have guessed the killer's identity if I hadn't already seen the 1940's movie before reading this. However, there are some significant differences in the movie and book so there were some things I never saw coming. Really intriguing locked room mystery! I recommend everyone give it a read....more