Miss Marple is an amateur detective from the fictional village of St. Mary Mead. Physically, she conforms to the stereotype of a benign “old woman” with “snow-white hair and a pink crinkled face and very soft innocent blue eyes” (96). Miss Marple’s unassuming manner and pastime of knitting add to this innocuous impression.

Miss Marple’s appearance and demeanor belie her true nature, meaning others often underestimate her. While she is kind, she is also shrewd and capable. Like Christie, Miss Marple is sharply observant of human nature, making her as “dangerous as a rattlesnake” to characters with something to hide (207). Miss Marple’s understanding of the dark side of human nature comes from a lifetime of observing life in her village. When meeting a new suspect, she invariably identifies a person from St. Mary Mead with similar character traits. These analogies often contribute to solving a case.

Although she can be considered the novel’s protagonist, Miss Marple is not introduced until Chapter 8 of A Murder Is Announced. Even then, her appearances are low-key and intermittent. Nevertheless, she plays a vital role in solving the mystery. Miss Marple’s unobtrusive presence is the very quality that makes her so effective as a detective.