Murder in the willet family Lt. valcour mystery series, book 4.

An extortionist's note, demanding $20,000 in cash and threatening the kidnapping of Kate Willett's two mentally unbalanced sons, sent Lieutenant Valcour rushing up to the Willetts' Adirondacks camp. There, death struck with slashing suddenness while Valcour was talking to young Arthur Willett, who was sprawled on a sofa smoking a cigarette. Listening to the crackling roar of flames in the fireplace, Valcour detected the odor of burning cloth. He...