The Arms Maker of Berlin

A ruthless arms billionaire and a disgraced history professor share a terrible secret.
Nat Turnbull is dragged abruptly from his quiet academic life when his former mentor Professor Gordon Wolfe is arrested for stealing top secret archive documents dating back to the Second World War.
Coerced into examining the archives for the FBI, Nat finds intriguing references both to Wolfe's activities in an Allied intelligence office in Switzerland during the war, and to a mysterious student resistance group in Berlin known as the White Rose.
Following Wolfe's cryptic clues to Europe, soon Nat is in a desperate race to unlock the truth, before it gets him killed.