The 1979 murder of a schoolteacher who was stabbed to death in a wooded area is reopened when the victim's bloodstained jacket is found stuffed in a tree trunk with a happy-face key chain in a pocket. The case was originally investigated by Jeffries when he was a rookie detective.

Lilly investigates the 1964 murder of a 17-year-old girl who was sent by her parents to a home for unwed mothers, where she gave birth to a girl. The next day the teen was killed. The case is reopened when the victim's daughter comes forward, having just learned that she was adopted and that her biological mother was slain.

When the victim's younger sister comes looking for her, the team re-opens the 2006 case of a missing Amish girl who was murdered while she was in Philadelphia experiencing the Amish rite of passage called "rumspringa".

The team re-investigates the suspected 2007 murder of a bride-to-be who was kidnapped on the day of her engagement party. Lilly and Scotty travel to West Virginia to escort the prime suspect to Philly, and on their way back, they hear his side of the story.

The 1960 murder of a stewardess who was attempting to organize a union is investigated, and the probe uncovers several hostile suspects who strongly resented her.

The team re-opens the case of the first ever female cadet in a local military school who was murdered in 2005.

The investigation into the female cadet's murder continues. As the team finds more and more clues, the killer tries to stop the investigation to remain hidden.