Finally, the last mystery in the case began to unravel… Dateline new tonight at 9/8c on NBC | Dateline NBC

It was a detective's nightmare, with no suspects in sight. Until... Find out what happened Friday at 9/8c on a classic Dateline mystery. | Dateline NBC

Tonight on a new Dateline, the latest chapter in this hair-raising tale, featuring new evidence, explosive testimony and the prosecution's new star witness. Watch at 9/8c on NBC. | Dateline NBC

On the morning of July 11, 2006, Mary Cooper and her daughter Susanna Stodden were murdered on a trail northeast of Seattle, Washington. More than 12 years later, their murders remain unsolved. David Stodden, Mary’s husband and Susanna’s father, tells Dateline about his search for justice. | Dateline NBC

In 2006, Dayna Herroz’s only child and grandchild were murdered. Josh Mankiewicz catches up with Dayna in the latest episode of “After the Verdict,” available exclusively to Dateline Premium subscribers on Apple Podcasts. Listen here: http://apple.co/datelinepremium | Dateline NBC

The case shifted from a missing person investigation into a homicide... The full story on Dateline tonight at 9/8c. | Dateline NBC