José Ferrer directed and starred in the fourth of several films made about the Dreyfus Affair, a cause célèbre in 19th century France, in which Alfred Dreyfus, a Jewish captain in the French army, was wrongly accused, and convicted, of spying for the Germans. The real spy was part of the investigation, but when he was revealed, the army covered it up. Novelist Émile Zola wrote an open letter to the prime minister of France entitled J'Accuse...! which exposed the truth behind the cover-up, causing a worldwide sensation. Unlike earlier interpretations, Gore Vidal’s screenplay was based on the detailed, in-depth book Captain Dreyfus: Story of a Mass Hysteria (1955) by Nicholas Halasz. Though the result was a box office disappointment that received tepid reviews, Vidal considered it one of his more successful adaptations, and today the film remains one of the most accurate versions of events as well as a charged response by Ferrer to his own public accusations by the House Un-American Activities Committee’s Communist witch hunt.