“Sir!” The butler sprang to his feet.

“Do not excite yourself,” said Poirot placidly. “Do not play the farce of the honest, injured man. You know all there is to know about the blackmail, is it not so?”

“Sir, I⁠—I’ve never⁠—never been⁠—”

“Insulted,” suggested Poirot, “in such a way before. Then why, my excellent Parker, were you so anxious to overhear the conversation in Mr. Ackroyd’s study the other evening, after you had caught the word blackmail?”

“I wasn’t⁠—I⁠—”

“Who was your last master?” rapped out Poirot suddenly.

“My last master?”

“Yes, the master you were with before you came to Mr. Ackroyd.”