The Prisoner (1955)

A Cardinal is arrested for treason against the state. As a Prince of his church, he's a popular hero of this people for his resistance against the Nazis during the war, and his resistance after his country again fell to another totalitarian conqueror. In prison, his interrogator is determined to get a confession of guilt from the strong-willed man, and thus destroy his power over his people. The verbal and psychological battles are gripping and powerful, not even the increasing pressures put upon the Cardinal can force him to weaken, not even solitary confinement, continuous blazing light in his cell, sleeplessness, efforts to persuade him he is going mad. And yet, in the deepening conflict, the superbly indomitable prisoner creates a tremendous pity on his tormentor.