The Margin — John C. Boland

Richard Welles, the younger son of a Baltimore investment-banking family, is out for a rough-weather sail with his wife Anne when they rescue the young daughter of a real estate tycoon from a plane crash in the Chesapeake Bay. The child's father, Harry Wollenschaft, asks for help in a small financial matter, entangling Richard and Anne in a game of big-time money and murder. First paperback edition of 1995 hardcover.