The season 33 premiere of Dateline investigates the case of a young Ohio woman who vanishes one summer night prompting her community to conduct a massive search. When she's found dead, investigators question her friends and family to uncover her killer.

INTERVIEWS WITH: Ally & Dave Markham, Investigator Paul Newton, Reporter Karin Johnson.

A 16-year-old calls 911 to report a break-in at her family's home. When police arrive, they discover her mother has been murdered, launching a years-long investigation that featured a false confession and revealed a dangerous romance.