In 1992, Halloween was cancelled in Oil City, Pennsylvania. Just days before, an 11-year-old was kidnapped and brutally murdered. The small town is rocked when Shauna Howe's body is discovered under a bridge, and investigators scramble to figure out what kind of person could have committed such a horrific crime. For two decades, the case goes unsolved despite the killer's taunts, solid DNA evidence, and a haunting copy-cat murder. When one investigator finds a single overlooked detail 20 years later, he discovers who killed Shauna Howe.