“Yes, the case is clear enough now; but, see you, I shall have a good deal of difficulty in proving it. Whalley was killed by order of the Big Four⁠—but not by Grant. A very clever man got Grant the post and deliberately planned to make him the scapegoat⁠—an easy matter with Grant’s prison record. He gave him a pair of boots, one of two duplicate pairs. The other he kept himself. It was all so simple. When Grant is out of the house, and Betsy is chatting in the village (which she probably did every day of her life), he drives up wearing the duplicate boots, enters the kitchen, goes through into the living room, fells the old man with a blow, and then cuts his throat. Then he returns to the kitchen, removes the boots, puts on another pair, and, carrying the first pair, goes out to his trap and drives off again.”

Ingles looks steadily at Poirot.

“There’s a catch in it still. Why did nobody see him?”

“Ah! That is where the cleverness of Number Four, I am convinced, comes in. Everybody saw him⁠—and yet nobody saw him. You see, he drove up in a butcher’s cart!”