From the book, "There was nothing in that clear, calm day, with its blue sky and its flooding sunshine, to suggest in the slightest degree the awful tragedy so close at hand--that tragedy which so puzzled the authorities and which came so close to wrecking the happiness of several innocent people." Harry and Gerry are friends and also rivals. The object of their affection is one Viola Carwell. Violas father is cool towards Harry, since his family got the best of him in a business deal. The story takes a sinister turn when Violas father dies on the golf course and the cause was poison. Was it suicide due to financial reverses? Or was it murder? The detective Colonel Ashley is called in to assist with the investigation.