The amazing true story of Frédéric Bourdin, who, after having plundered all the centers for runaway minors and delinquents in Europe, even though he has come of age, now passes himself off as Nicholas Barclay, a 13-year-old American who vanished three years ago. To his astonishment, Nicholas's family welcomes him like their son, leaving Interpol and the FBI aghast. It is the beginning of a race against time for the investigators, family, and Bourdin.