Barely out of the psychiatric hospital where he went to seek care, Gilbert Nodier commits several assaults to have some money.

A series of murders is committed in Nice on the French riviera. The commissaire Carella is in charge and tries to find a missing link between all these murders.

When a man's best friend is shot in cold blood by two corrupt policemen, he must track down the only eyewitnesses, who have deported to Mali.