There’s an elderly woman who disappears. A village that, behind all its gossip, hides a dark secret, a house split in half, tombs that are better left untouched, a doll that reappears from the past, a terrifying lawyer who wears a death mask. It will take some doing for Prudence and Bélisaire Beresford, who have Hercule Poirot’s patience and Agatha Christie’s humor, to uncover the astounding truth. “By the Pricking of My Thumbs” is the last in a series of four adventures of the duo invented by Agatha Christie.