1 For her first novel, The Mysterious Affair at Styles, Agatha Christie wanted her detective to be "someone who hadn’t been used before." Thus, the fastidious retired policeman Hercule Poirot was born—a fish-out-of-water, inspired by Belgian refugees she encountered during World War I in the seaside town of Torquay, where she grew up. When a later Poirot mystery, The Murder of Roger Ackroyd, was adapted into a stage play, Christie was unhappy that the role of Dr. Sheppard’s spinster sister had been rewritten for a much younger actress. So she created elderly amateur detective Jane Marple to show English village life through the eyes of an "old maid"—an often overlooked and patronized character. How are Miss Marple and Monsieur Poirot different from "classic" crime solvers such as police officials or hard-boiled private eyes? How do their personalities help them to be more effective than the local authorities? Which modern fictional sleuths, in literature, film, and television, seem to be inspired by Christie’s creations?

2 Miss Marple and Poirot crossed paths only once—in a not-so-classic 1965 British film adaptation of The ABC Murders called The Alphabet Murders (played, respectively, by Margaret Rutherford and Tony Randall). In her autobiography, Christie writes that her readers often suggested that she should have her two iconic sleuths meet. "But why should they?" she countered. "I am sure they would not enjoy it at all." Imagine a new scenario in which the shrewd amateur and the egotistical professional might join forces. How might their investigative styles conflict with or complement each other?

3 Despite Christie’s popular success, professional critics have not always been kind. A review of Christie’s play Verdict, on tour in the U.K. in 2011, begins, "The fascination of an Agatha Christie whodunnit is the plot. It’s an intellectual maze with twists and turns and dead ends, literally. Most of the characters are two-dimensional, at best." This is not the first time Christie has been "accused" of focusing more on puzzle than people. Which do you feel is more important in a murder mystery and why?

4 In the Masterpiece Mystery! films, which characters do you feel are fully developed and multidimensional? Which could have been made more complex? In an interview, David Suchet reveals that he found the inspiration for his character’s unique walk in an offhand description by Christie: "Poirot crossed the lawn with his usual rapid, mincing gait, with his feet tightly and painfully enclosed within his shiny patent leather shoes." Suchet’s physical interpretation of this passage allows us to, literally, walk in Poirot’s shoes. How else do the actors flesh out the personalities of Christie’s creations?

5 In addition to 80 books, Christie wrote 19 plays, one of which, The Mousetrap, opened in the West End of London in 1952 and has been running continuously ever since. Her novel Three Act Tragedy spotlights Christie’s love of the theater even as it sends up the quirks and conventions of the arts. The novel is divided into "acts" and begins as if it were a theater program, with credits for direction, costume design, and, ultimately, "Illumination by Hercule Poirot." How do the filmmakers create this connection to the theater onscreen? Does this treatment enhance or detract from the tension of the plot? In the beginning and end of the film version, but not in the book, Poirot says, "Our revels have ended"—a line, spoken by Prospero in The Tempest, thought to be Shakespeare’s own farewell to the theater. How does this quotation relate to the theme of the story?

6 Unlike the book, the film Three Act Tragedy gives Poirot a larger role and suggests that he and Charles Cartwright, a famous actor now retired, have been friends for many years. How does this deeper relationship affect Poirot’s investigation and its outcome? Why does Poirot react so emotionally at the end? How does this influence your view of his character?

7 The Pale Horse opens with images of the dying and distressed Mrs. Davis crosscut with Miss Marple listening to a radio broadcast of Macbeth. We hear the scene in which the three witches predict the Scottish lord’s fate. Why do you think the filmmakers chose to open the film this way? How does this reference to the Shakespeare play tie into the plot?

8 The time period, setting, and final twist of the film adaptation of The Clocks are very different from the novel. The original, published in 1963, takes place in a nondescript town near a naval base as the Cold War is heating up; Sheila Webb’s true parentage is revealed at the end. The film gives us the dramatic Dover coast in the 1930s, sets up the threat of a second world war, and leaves Sheila’s identity unresolved. How do these differences affect your response to the film? How did these changes strengthen, or weaken, the resolution?