Every so often someone will come into the store, look around stupefied, and say something along the lines of You mean all these books are mysteries? I usually point out that we could fill several bookstores our size with completely different mysteries, and the truth is that Aunt Agatha’s, crowded as it may appear, represents a mere drop in the vast ocean of mystery.
Since the defining era of Holmes and Poirot, the big fishes of these waters have been the series sharks, gobbling much of the available attention and profits with the continuing adventures of a single character or school of characters swimming their way through a number of books. But there are other currents in the genre, rising from the dark depths of the ghost story and the gothic, solitary self-enclosed novels where the seemingly placid surface of everyday life grows slowly menacing and powerful riptides and unpredictable squalls appear. In a way stand-alones are even more unpredictable than series books because in the former no character is guaranteed survival in order to play a part in a future installment – anyone can be killed – or be a killer.