When Bobby Jones and his girlfriend Lady Frances "Frankie" Derwent are playing a round of golf, Bobby knocks his ball over the edge of a cliff. He cannot find his ball again, but on the rocks below he discovers the body of a dying man. With his dying breath, the man opens his eyes and asks, "Why didn't they ask Evans?". Armed only with the image of a beautiful young woman found in the dead man's pocket, the amateur sleuths must try to solve the case.