Interpol and the Russian mafia are chasing Anthony Zimmer (Attal), a criminal genius responsible for money laundering in France. Zimmer has had extensive plastic surgery, and the only way to trace him is through his girlfriend Chiara (Marceau). When Francois, an ordinary man, speaks to Chiara on the train, he is mistaken for Zimmer, and thus becomes a target for the mob.
Anthony Zimmer was a big money launderer. The police wants him, but he has changed his face and voice. His old Russian clients want him dead. His ex is told to socialize with a random man on the train Paris to Nice.