Deaves

In the short story In the House of the Enemy (later, chapter 8 of The Big Four), Deaves was the valet of the American multi-millionaire Abe Ryland. He had been brought over from New York to England by Ryland but he was an Englishman by birth. Hastings was suspicious of him and believed it was Deaves who (under the assumed named of George) ambushed him and Poirot at the quarry.