In November 1978, an old man unknown to the general public, Ruhollah Khomeini, arrived in France. In just a few months, from Neauphle-le-Château, he orchestrated the fall of the Shah and the birth of the Islamic Republic of Iran. Since then, attacks, hostages, secret negotiations, and a diplomatic Cold War have fueled forty years of troubled relations between Paris and Tehran. Even today, one question remains: is Iran an ally... or an enemy?