Les Verrières. In a decaying suburb, slogans suddenly appear on the walls demanding justice for Said, who lost his life at the age of fifteen. Eleven-year-old Mattia Lorozzi tries to uncover what happened and encounters a world filled with hatred, sorrow, and lies. He no longer has a father and lives with his guardian, Zephyr Palaisot, a twenty-four-year-old night watchman, and his suicidal girlfriend Gabrielle in an apartment. His mother has not been in touch for weeks, and his sister is traveling, only to return at Christmas. A psychiatrist is overseeing Mattia to prevent him from being placed in a home. Two men are lurking around him and his guardian. He cannot turn to the police, as they are not well regarded in Les Verrières, having failed to protect the young Said Zahit fifteen years ago.