As the flames of war engulf the Continent in 1940, refugees from the war torn countries flee to Lisbon, the melting pot of Europe. A Pan American Captain is brutally murdered in Lisbon. His friend, Curtis Westbrook, senior Captain for Pan American,flies to Lisbon seeking clues about the murder, but he is soon caught up in the maelstrom of a dangerous and secret mission hatched by President Roosevelt in the desperate attempt to preserve the hopelessly divide French Resistance and the exiled Charles DeGaulle. Westbrook flies the huge flying boat,the Yankee Clipper, from Lisbon to London at the height of the Battle of Britain. The authoris a former Naval Aviator and through the courtesy of The Boeing Company, was given a copy of the operating manual for the Boeing Clipper which greatly enhanced the flying scenes.