In watching The Big Fix last night (Richard Dreyfus, late seventies) he, as a detective, comes upon a door that is ajar and, of course, there is a dead body inside. Sometimes it's only that the place has been ransacked, but you know the scene. This scenario is probably rare in life. Most criminals want to keep their crime a secret for as long as possible. So why is this device used so much in fiction? Is there an inherent drama in it that makes its ubiquitousness worth it? Is its use actually an hommage to other crime novels/movies?