This book collects a few of Chandler's short stories together, along with the essay that gives the book its title. The essay reads well, and gives a simple, clear statement of what Chandler dislikes about the murder mystery genre. You can read the details for yourself, but I'll give you a clue: read Hercule Poirot or Miss Marple, then one of these stories. The differences fix the problems that Chandler saw in the genre as it existed before him.