Les mois d'avril sont meurtriers (1987)

When an informer is executed, his dismembered remains found in several bin bags, Fred, a resilient police inspector, leads the murder investigation with his customary dogged determination. Fred has been with the police service thirty years and despite his own personal tragedies he remains committed to his profession. The more sordid and vile the crime, the more determinedly he sets about bringing the culprit to book. Fred's prime suspect is Gravier, a former butcher turned military man. Despite Fred's repeated attempts to intimidate him, Gravier retains his cool and the two men are soon drawn into a private battle of wills. With the help of an alcoholic prostitute, Fred finally manages to make his arrest, but his certainties are badly shaken when Gravier manages to gain his release. This unexpected development makes Fred all the more resolved to punish his opponent. Haunted by the death of his daughter, disgusted by the conflict of interests that have allowed his enemy to evade the law, Fred goes after Gravier for their final bloody showdown.