Dr. Sheppard, the narrator of the novel, uses the puzzle metaphor to describe the mystery of Ackroyd’s murder:
It was rather like a jigsaw puzzle to which everyone contributed their own little piece of knowledge or discovery. But their task ended there. To Poirot alone belongs the renown of fitting those pieces into their correct place. (164)
The clue-puzzle mystery is Agatha Christie’s specialty, and the surprising plot twist her forte.
Christie is cunning in her use of misdirection. The red herrings that characterize her plots make these stories realistic and convincing. All the suspects in The Murder of Roger Ackroyd exhibit some form of suspicious behavior. Poirot tells them, “Each one of you has something to hide” (154). These secrets complicate the plot and take us down numerous blind alleys. Christie is cunning in her use of misdirection.
Hercule Poirot’s eccentricities cause characters to underestimate his talent as a detective. Dr. Sheppard and his sister initially mistake him for a retired barber. Poirot always succeeds in solving crimes but rarely looks as if he will. He admits using old-fashioned methods, yet these methods produce results. His favourite line is: “I work only with the little gray cells” (261). Poirot is far ahead of both readers and characters in recognizing the significance of minor clues. Like his predecessor, Sherlock Holmes, Poirot uses superior reasoning ability to interpret clues and solve cases.
The action of the novel is presented through the eyes of Dr. Sheppard, an unreliable narrator. The narrative voice is a masterful touch in the novel, fully