Can a lie become a clue to uncovering a criminal? Rich and sick Laura Welman died suddenly. Her property is apparently inherited by her lovely niece Elinor. But did her aunt really not want to bequeath her fortune to someone else? Another death raises more suspicions, and Elinor is finally accused of murder. Only one person does not believe that she committed it, and calls Hercule Poirot. However, instead of searching for the truth, he begins to ask surprising questions: What causes people to lie? What can be deduced from their lies? Why do even the innocent lie? Once he knows the answers, he uncompromisingly exposes the killer.