First thing in the morning, old, wealthy and generally disliked Angus Clyde is found by his manservant in his bedroom armchair murdered by gunshot to the head. Police Inspector Carr turns to his old friend, psychologist Dr. Amos Crabtree, to assist in the investigation. The four primary suspects are the people who attended a dinner with Angus at the Clyde household the previous evening: Ann Clyde, Angus' much younger wife who would probably admit that she didn't love him; Ann's drunkard brother Larry Merton; Ann's former schoolmate and former fiancé, Captain Dick Rugg who admits to still loving Ann and who Angus was jealous of since he probably knew Ann loved Captain Rugg in return; and Eric Muller, who wanted to purchase the Imperial Diamond owned by Angus, who in turn refused to sell. While Carr is swayed by the obvious which points in the direction of one of the suspects, Crabtree digs beneath the surface to discover the real killer.
—Huggo