MR. SHAITANA “My dear Monsieur Poirot ! ” It was a soft purring voice - a voice used deliberately as an instrument - nothing impulsive or unpremeditated about it. Hercule Poirot swung round. He bowed. He shook hands ceremoniously . There was something in his eye that was unusual. One would have said that this chance encounter awakened in him an emotion that he seldom had occasion to feel .