"Norris Jordan uncovers a fiendish plot and is about to give evidence to the British Government - but on his return to England he is murdered.
Having anticipated this, however, he has concealed his evidence within an elaborate series of riddles, each leading to a scrap of vital information; the first going to his friend, Peter Clayton.
Aided by Michael Dene, the head of the Secret Service, Clayton struggles to solve the riddles - but the duo soon find that their very lives are at stake as the plotters try to silence them..."