The Rhinemann Exchange
by Robert Ludlum
On the eve of the Second World War, David Spaulding, a radio voice actor, is recruited by Colonel Ed Pace to run a secret network in Lisbon.
The plot advances to 1943. Both the Allies and the Axis find themselves facing key shortages that impede their ability to win the war. The Allies lack gyroscopes capable of operating at high altitudes; thus they are losing an unacceptably high number of bombers. If they do not procure gyroscopes soon, the D-Day invasion of Normandy will need to be postponed. The Germans find themselves without high quality diamonds, which are necessary for the rocket development program at Peenemünde.
Ironically, each side has what the other needs: the Allies control access to high quality diamonds from the Belgian Congo; the Germans have a design for a gyroscope able to operate at high altitudes. The German intelligence agency, the Nachrichtendienst, discovers that the Allies are in need of gyroscopes, and proposes an exchange, to take place in neutral territory: Buenos Aires, Argentina.
David Spaulding has, in the meantime, become an invaluable spy for the Allies. His Lisbon network ferries agents and defectors back and forth from German occupied territory. He is selected, however, to oversee the receipt of the gyroscopes - critically, he does not know that diamonds are being exchanged for the gyroscopes.
The Germans select the exiled industrialist Erich Rhinemann to supervise the exchange at their end. He is a clever choice because, although he is Jewish, he is committed to German victory and believes that he will be welcomed back after a German victory. Rhinemann is immensely influential and powerful in Buenos Aires.
Although puzzled at his assignment away from Lisbon, Spaulding accepts his new assignment. However, there are several attempts made on his life: one occurring at an airfield in the Azores, another in New York City. While he is in New York, awaiting details on his assignment, he encounters an old flame, Leslie Jenner Hawkwood who, having drawn him away from his apartment, seemingly vanishes into thin air. Spaulding's mentor, Ed Pace, is meanwhile murdered.
Upon arrival in Buenos Aires, Spaulding meets and falls in love with Jean Cameron, a woman employed by the embassy. Attacks on him continue, and he suspects he is being trailed by the Gestapo. He meets with Rhinemann to acquire the gyroscopes, but tries to draw out his mysterious assailants - Rhinemann and the other Germans are adamant that the Gestapo is not active in Buenos Aires.
To his profound shock, Spaulding discovers that the people trying to stop him work for the Haganah, a Jewish para-military organization set on stopping the exchange. When he captures Asher Feld, the Haganah leader, Feld informs him that he is a party to an exchange of diamonds for gyroscopes. From then on, Spaulding decides that the exchange must be stopped. He pretends to carry out his end, all the while facilitating a Haganah attack on Rhinemann's estate. Spaulding succeeds in killing Rhinemann (who had planned to kill him after the exchange) and Rhinemann's Nazi controller. Having acquired incriminating evidence about the exchange, Spaulding blackmails the Americans who had arranged it and arranges to retire with his beloved Jean.