Blood on the Moon — James Ellroy

Detective Sergeant Lloyd Hopkins can't stand music, or any loud sounds. He's got a beautiful wife, but he can't get enough of other women. And instead of bedtime stories, he regales his daughters with bloody crime stories. He's a thinking man's cop with a dark past and an obsessive drive to hunt down monsters who prey on the innocent. Now, there's something haunting him. He sees a connection in a series of increasingly gruesome murders of women committed over a period of twenty years. To solve the case, Hopkins will dump all the rules and risk his career to make the final link and get the killer.