Dateline: Unforgettable

Keith Morrison recalls how a deadly high-speed chase in Montana led “Dateline” on a search to unravel a mystery unlike any he has told, one where a missionary turned into a monster and committed one of the state’s most notorious crimes.

A mystery in paradise unfolds when Sarm Heslop vanishes from her boyfriend's yacht. In a case that made international headlines, Andrea Canning recounts her memorable journey searching for a particular person of interest.

A 911 call reporting an apartment break-in holds the key to solving the mysterious murder of a young graduate student named Katie Sepich; her case contained many twists, and her family's grit still astonishes Josh Mankiewicz.

When Tina Sandoval disappears, her parents and loved ones spend years searching for her; Dennis Murphy takes a fresh look at the secret Tina kept and at the demon who forced her loved ones to make an agonizing decision.

The survivor of a horrible attack is convinced the police on the case have the wrong suspect. Keith Morrison looks back on his heart-wrenching interview with the victim and her courageous quest to uncover the truth.

After Todd Chance is murdered, police follow a trail of video evidence to track down their suspect. Andrea Canning recalls a particularly revealing interview, including an eye-popping detail you must see to believe.

When Josh Mankiewicz gets asked about his most memorable stories, the name Dayna Herroz comes to mind; after her daughter and 10-month-old grandson are murdered, her quest for justice ends with a twist in a San Diego courtroom.

A Florida father is determined to find out what happened to his daughter after her fatal fall from a penthouse apartment; Dennis Murphy revisits the dramatic events as this dad confronts overwhelming obstacles to learn the truth.

When three people are found dead on the same day in a Kentucky town, investigators know that it isn't a coincidence; years pass before an arrest; Keith Morrison reflects on the triple murder that shook a tight-knit community to its core.

The fatal shooting of NBA star and hometown hero Lorenzen Wright sends shockwaves through the city of Memphis, Tenn.; Andrea Canning takes a new look at the diabolical plot behind Wright's murder and his family's tireless fight for justice.

Clues at the crime scene seemed to point in one direction. "The twist that came next was one this town would never forget," Dateline Correspondent Josh Mankiewicz said of the shocking murder of Sonya Ivanoff.