The Rules of Detective Fiction
During the Golden Age of Detective Fiction writers tried to set up “Rules” for the genre to ensure “fair play” for the readers. Agatha Christie, as well as other authors, broke the rules many times.
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There simply must be a corpse in a detective novel, and the deader the corpse the better. No lesser crime than murder will suffice. Three hundred pages is far too much pother for a crime other than murder. After all, the reader's trouble and expenditure of energy must be rewarded.
Fandom.com seems like such a garbage pile; I’m surprised to see something like this there.