The corpse in a diving suit of Pierre Saint-Florent has been found in a beach near Martigues.Elisabeth Richard, district attorney and Paul Jansac ,police officer, are in charge of the investigation of that death.Pierre Saint-Florent is the son of Jean-Charles Saint-Florent, who has a fuel transport company in Martigues; Pierre has a fishing company and is a divorced man: his ex-wife Catherine manages a restaurant.Little by little Elisabeth and Paul know the people who have had relations with Pierre; Michel Lecouffre, a chatterbox and manager of a diving company, Simon Chastaing, another fisher of Martigues , Matthieu Bidard , a drug dealer , and the family Dos Santos.At the burial of Pierre Saint-Florent Gwendoline Dos Santos was broken and went away the church.