Reading progress update: I've read 30%.

Fortunately, in the course of his career, Hercule Poirot had made friends in many counties. Devonshire was no exception. He sat down to review what resources he had in Devonshire. As a result he discovered two people who were acquaintances or friends of Mr Meredith Blake. He descended upon him therefore armed with two letters, one from Lady Mary Lytton-Gore, a gentle widow lady of restricted means, the most retiring of creatures; and the other from a retired Admiral, whose family had been settled in the county for four generations.
WooHoo! A nod to Lady Mary of Three Act Tragedy!