Ousmane Diakité and François Monge are two cops with very different styles, backgrounds and careers. The unlikely pair are reunited once again for a new investigation that takes them across France. What seemed to be a simple drug deal turns out to be a much bigger criminal case wrapped in danger and unexpected comedy.

After a gifted musician inherits a mansion after her long lost father dies under mysterious circumstances, she discovers his last musical masterpiece riddled with cryptic symbols that unravels an evil secret, triggering dark forces that reach beyond her imagination.