Beloved private eye Hercule Poirot takes on an international crime cabal in this novel by the author who “created the modern murder mystery” (The New Yorker).
 
At home in London, detective Hercule Poirot is visited by a stranger whose repeated, incoherent ramblings and scribblings of the number four are most alarming—especially when the uninvited guest collapses to the floor. Grasping at the meaning behind his visitor’s words, Poirot soon puts his infamous “little grey cells” to work to track down four criminal masterminds intent on global domination. Reunited with his dear friend Captain Hastings, Poirot embarks on a journey that takes him from England to France and beyond. Suddenly submerged in a world of international espionage in the name of uncovering the dark truth about the Big Four, Poirot risks not just his self-proclaimed reputation as “the great mind in Europe,” but his life.
 
“It is always a delight to meet Hercule Poirot again. He is one of the few detectives with real charm.” —Dorothy L. Sayers, author of the Lord Peter Wimsey mysteries
 
“The acknowledged queen of detective fiction.” —The Observer