In September 1939, as Warsaw falls to the Wehrmacht, Captain Alexander de Milja is recruited to Poland's newly formed underground army, the Związek Walki Zbrojnej (ZWZ), or the Union of Armed Struggle.

His first mission is to smuggle the national gold reserves out of the country by means of a refugee train to Bucharest.

These see him collude with fellow saboteurs in the back alleys and black-market bistros of Paris, working with the underground in the tenements of Warsaw, assisting the British attack on German naval targets in the harbor of Calais, and teaming with partisan guerrillas in the frozen forests of Ukraine.

His family belongs to the Polish aristocracy, and he is a graduate of the elite French military school Saint-Cyr.

Working as a cartographer in the Polish military before the fall of Poland, De Milja is then recruited to the underground, where his exploits see him assume various aliases; he passes at any one time as a Russian writer, a Slovak coal merchant, or a Polish horse breeder.