Acting on the information from a suspect captured in Algeria, Detective Geneviève Benoit and her partner Detective (Captain) Claude Lemieux begin tracking the movement of members of 'Papillion Transport', a mysterious shipping firm transporting drugs throughout the Mediterranean. While investigating Papillion Transport, they learn of a plot to kidnap a French police officer by Italian mafia members. Along the way, they become involved in a gun battle with the Algerian drug smuggler Nazim Aziz in an attempt to free one of his own from the police.