“The American stranger. He may have been in league with Parker, and possibly in Parker we have the man who blackmailed Mrs. Ferrars. If so, Parker may have heard enough to realize the game was up, have told his accomplice so, and the latter did the crime with the dagger which Parker gave him.”

“It is a theory that,” admitted Poirot. “Decidedly you have cells of a kind. But it leaves a good deal unaccounted for.”

“Such as⁠—?”

“The telephone call, the pushed-out chair⁠—”

“Do you really think that latter important?” I interrupted.

“Perhaps not,” admitted my friend. “It may have been pulled out by accident, and Raymond or Blunt may have shoved it into place unconsciously under the stress of emotion. Then there is the missing forty pounds.”