To his family, François Voisin is nothing more than a humdrum civil servant. In truth, for the past twenty years he has been working as a secret agent. All goes well until circumstances put his secret in danger.

The movie takes place in a poverty-stricken, rent-controlled neighborhood on the outskirts of Paris. Algerian immigrants, many of whom are in France illegally, the place has earned the nickname of "100%Arabica". It's a rough neighborhood - crime is rampant, gangs of juvenile delinquents roam the streets, and the police are afraid to patrol the area. When the out-of-touch mayor decides that he wants to restore order to the area, he offers a subsidy to Slimane, the imam of the local mosque. If Slimane can get people off the streets, the mayor will continue the payments. Soon the byways of 100%Arabica are almost peaceful - but not because of something Slimane has done. The reason is that a new Rai Band, Rap Oriental, has taken the neighborhood by storm...

Jacques Mesrine, a loyal son and dedicated soldier, is back home and living with his parents after serving in the Algerian War. Soon he is seduced by the neon glamour of sixties Paris and the easy money it presents. Mentored by Guido, Mesrine turns his back on middle class law-abiding and soon moves swiftly up the criminal ladder.