"M" Is for Malice (1996)

Kinsey Millhone is hired to find the black sheep of the Malek family after the death of his multi-millionaire father. Guy Malek had been a ne'er-do-well rebel, who had finally tried his father's patience too far twenty years before, and been thrown out and never heard from since. His unlikeable brothers do not want him back in their lives, and especially do not want him taking a share of the millions they feel he did not deserve. Yet the man Kinsey tracks down has changed his life radically and seems to be the best of the Malek boys. His reappearance, followed within days by his murder, opens up wounds which had been hidden for decades.

At the same time, Kinsey is trying to cope with her own personal problems, not helped by the reappearance in her life of Robert Dietz, the attractive but non-committing private investigator with whom she had had a previous relationship.