説明
"The man who climbed in through the window of Bookmaker King's home in Minneapolis claimed that, by the aid of his artificial ear-drums, he could hear sounds totally inaudible to ordinary people, and by listening could manipulate any combination lock and open any safe. What happened when the occupant of the house bade him open Mrs. King's safe and render her diamonds available forms the climax of as swiftly-moving and dramatic a story as even Keeler has ever written."