In this remarkable 1927 novel by E. Phillips Oppenheim, a great conference has been called in London to renegotiate the war debt. It is clear that Germany is suffering, and all of Europe is affected. The great Financier Felix Dukane is in London with his beautiful daughter Estelle. It is rumored that he stands ready to loan Germany One Billion Pounds if the conference is able to limit the total debt.

The young American socialite Mark van Stratton has been living in Europe since the end of the war. He is close friends with English and French diplomats, but has done nothing useful with his life. A chance meeting between Mark and Estelle sets his life on a new course.

The outcome of the conference hinges on military and industrial secrets. The remarkable accuracy of Oppenheims depiction of German militarism (writing in 1927) and his predictions of the timing of World War 2 are uncanny. He describes the "Club of 1940" which is a German secret society dedicated to destroying France.