Wealthy Charles Moneymaker and his companion, James Reading, son of a famous railroad magnate, spend their spare time solving murders. A Christmas holiday invitation from an old friend of Moneymaker seems innocent enough in the beginning. They begin to wonder if there was a method to some madness as other guests, one-by-one, are murdered. Some evil and diabolical game is afoot. Can they figure out what's happening before the killer is the only one left?