In his fourth appearance, Matthew Scudder deals as an unlicensed private investigator with a case from his own past as a cop. A serial killer has confessed to the murder of seven woman, but insists he had nothing to do with the death of an eighth victim. The dead woman's father hires Scudder to investigate, and the facts he uncovers tend to confirm the killer's claim of innocence. This tells him a new killer purposely copied earlier crimes-which makes it likely he had a personal motive. Scudder,