Mercenary Richard Brumeire, aka "La Mist" (codename "The Mist"), was once a mysterious French Secret Service agent. He was forced to return to his old ways because the immunity he had obtained for his son Archibald 25 years ago was revoked. A criminal activity threatens Archibald's life. In order to save his son, Richard has no better choice but to turn to his old acquaintances and work with a group of reckless young people and an alternative bureaucrat. But the most important thing for Richard is to muster the courage to let Archibald know that he is his father.