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.

Two Korean ex-pats in Paris are recruited by a French mobster. The duo find themselves at war with their mobster recruiters and each other.