Lily re-investigates a 1980's murder where a young housewife was blown up by a bomb in her backyard. Meanwhile, the victim's now-grown daughter is bothering a pervert whom she believes is the killer, but is he?
When a serial rapist sends a letter to the squad announcing his return to Philadelphia after five years, the team re-investigates the 1998 murder of a college student who was believed to be one of his victims.
A petty crook, Ricky (Tim deZarn), hoping to get a reduced sentence, relates witnessing a young man washing blood out of his car the night a teen track runner was murdered. The young athlete, Paige Pratt (Summer Glau), was found shot, and her boyfriend Al Clarkson (Doug Kruse) was originally imprisoned for the crime.
After two years in a coma, a mother wakes in the hospital. Rosie hardly remembers the night she and her daughter were thrown out of a window, killing her daughter. Lily and Scotty look into the case and find a whole nest of bad secrets.
The team is searching for as suspected serial killer. The murders started with a young man who was hitchhiking home from the casino after winning $3000. They have little to go on other than a boot print.