Paris, Kingdom of France, August 18, 1572. To avoid the outbreak of a religious war, the Catholic princess Marguerite de Valois, sister of the feeble King Charles IX, marries the Huguenot King Henry III of Navarre.

The true story of Rosario Livatino, a young judge in Sicily in the early 1980s, who have been nicknamed 'The Boy Judge' from the President of the Republic. He's strictly incorruptible, working hard and refusing even to shake hands with suspects. He then starts a number of investigations that lead him to touch the mafia power in the area, and then to personal war with the hidden organization.