In Vienna, two people possess top secret documents stolen from a safety deposit box in Berlin: Gunther Radok, a dedicated police detective who now must break the law, and his lover, Frieda Lassen, a beautiful German-American concert pianist who is with the underground. Their mission is to get these horrifying papers, attesting to Hilter's genocidal program against the Jews, to the Allies.

One person knows of their plan. The most brilliant and ruthless secret agent the Nasiz have, a crack hunter and assassin, man whom even his superiors fear and whom Frieda once passionately loved. His name is Wolf Hartmann and he relentelssly pursues them through Austria from the darkest depths of Vienna's sewers to the treacherous mountain trails of the majestic Alps-to keep them from reaching the Swiss border....