Christopher Plummer is The Greatest Spy in History (1966) – World War II Film

Burglar Eddie Chapman (Christopher Plummer) is rotting in prison on the island of Jersey when the Nazis invade. A master manipulator, Chapman convinces the Germans to use him to spy on the British. And when the would-be traitor returns home, he persuades the English to employ him as a double agent in exchange for a full pardon. Thus begins the true and chilling story of a professional thief who became a devoted patriot of World War II.