In a small town at the foot of the Alps, heavy fog caused a traffic accident. The driver of the accident was Detective Vogel (played by Toni Servillo) who came to investigate the missing girl. The middle school teacher Martini (played by Alessio Boni) was the suspect he had locked on. Under the guidance of psychiatrist Floris (played by Jean Reno), Vogel slowly told the truth behind the scenes, and a bigger conspiracy that had been brewing for a long time gradually revealed its true face. Adapted from the world-bestselling thriller novel "The Girl in the Fog".