Marc Perrier

Childhood friends Jacques and Enzo share a passion for the danger of free diving. Jacques, following in the footsteps of his father, who died at sea when Jacques was a boy, harbors a remarkable ability to adjust his heart rate and breathing patterns in the water, with his vital signs more closely resembling those of dolphins than men.

Fred, a raffish safe blower, takes refuge in the Paris Metro after being chased by the henchmen of a shady businessman from whom he has just stolen some documents. While hiding out in the back rooms and conduits of the Metro, Fred encounters a subterranean society of eccentric characters and petty criminals.

With the help of journalist Diane Castelain, Parisian police inspectors Leo Gorce and Gu Arenas are trying to solve the murder of a member of the French Parliament, but some dangerous powerful people try to make sure that doesn't happen.