On a future earth where 98% of the surface is underwater, a Warlord who controls an army of sharks meets his match when he captures the daughter of a mysterious shark caller who must learn to marshal a supernatural ability if she is to free her people from the Warlord's dominion.

To be closer to his children following his divorce, Laurent Monier, a history and geography teacher in a peaceful provincial high school, accepts a position in a sensitive college in the Paris suburbs. He is assigned the hardest class, the fourth techno, and he finds an apartment in the Cité des Muriers, a particularly difficult district.