Dateline: Unforgettable

A case Keith Morrison can't forget in which a teen's murder shakes a Nevada community and two unlikely people confess.

When a police officer's wife is shot to death in her bed, her parents' certainty that investigators have it wrong and their determination to untangle the mystery, makes the case unforgettable for Josh Mankiewicz.

Andrea Canning recalls a case in which investigators set up an elaborate sting operation to stop a murder-for-hire plot.

A man charged with murder claims it was impossible for him to have committed the crime. For Dennis Murphy, the surprising courtroom strategy provides a memorable twist.

Keith Morrison reflects on the case of a Chicago woman from a big family who went missing. Investigators began to suspect a man in her life was full of secrets.

A detective makes it her mission to find dozens of women who vanished on the streets of Albuquerque, New Mexico. For Josh Mankiewicz, her resolve makes this story unforgettable.

After shedding hundreds of pounds, a popular kindergarten teacher goes missing. Investigators find a link between her weight loss and her disappearance. The case ranks as having one of the craziest motives Andrea Canning has heard.

This case has stayed with Dennis Murphy since he first reported on it: A determined young woman searches for answers in her mother’s mysterious death. Her decades-long quest leads to a dramatic courtroom decision.

Investigators track down a suspect in the disappearance of a celebrity dog trainer. Keith Morrison reflects on the fractured love story at the center of this mystery.

A wife calls 911 to report her husband has been shot on a country road in Texas. What she told investigators next makes this case memorable for Josh Mankiewicz.

Andrea Canning looks back on one of her most memorable cases where a fitness tracker helped detectives solve the mystery of a young woman's death in Wisconsin. Andrea confronts the killer in a tense interview.

When a star athlete at an Ivy League university goes on trial for murder, sparks fly in the courtroom. The trial ends with a stunning decision that Dennis Murphy will never forget, but the surprises in the case are just beginning.

A California woman's two former husbands are mysteriously murdered nearly 20 years apart. Keith Morrison reflects on the case that sent him halfway across the world on a hunt for answers.

When a complicated Texas love triangle ends in murder, a pink gun leads to an arrest. New evidence makes investigators rethink the case. Josh Mankiewicz has reported on two-timing before, but this case had a twist he has never seen.

When a small-town Alabama resident is murdered, rumors involving a local pastor begin to swirl. Andrea Canning reflects on this story that feels to her like a steamy soap opera playing out in real life.

Dennis Murphy reported on the twists and turns of the Jennifer Dulos case as they happened. He offers candid insight into his one-on-one interview with the prime suspect: Jennifer’s ex-husband, Fotis Dulos.

For Keith Morrison, this case stands out as an unusual mystery. The crime seemed arbitrary with no apparent motive. There was a confession which might have ended the investigation, but that was only the beginning.

A college student is found murdered and the case sits cold for nearly 40 years. Josh Mankiewicz reflects on the vow that keeps the case alive and the innovative method used to catch the killer.

An aspiring Playboy model is murdered in Miami, FL. A seven second clip of her last moments alive are caught on security video and could hold key clues. The haunting images make this case one of Dennis Murphy's most memorable.

A man claims his wife died by suicide, but a suspicious house fire 24 years later raises doubts; Josh Mankiewicz remembers the suspect who could not stop talking.

When a pastor loses a second wife in an accident, authorities become suspicious. Dennis Murphy returns to this unforgettable story of evil and betrayal, wondering how far this a man of God might have fallen. Dennis still can’t believe the answer.

Years after a Montana man is found dead, his son searches for answers. Keith Morrison cannot forget that son who opened a box, and faced a terrifying family secret.

After a 15-year-old girl disappears, investigators discover a creek where the local teenagers hang out. Dennis Murphy looks back on the case that kept him guessing until its astonishing conclusion.

Gary Hilton is a name Dennis Murphy will always remember. A hiker goes missing and authorities suspect Hilton is reenacting a slasher movie. Dennis reflects on the real-life murder spree that terrorized the American South.

Keith Morrison revisits a story that has haunted him for years; when detectives find a missing woman's car abandoned on a bridge, their investigation uncovers a tangled plot involving money, friendship, and a deadly betrayal.

A mother of two vanishes in Monrovia, CA. As detectives investigate, the woman's loved ones reveal that she feared she was being stalked. For Josh Mankiewicz, cases like these are all too familiar, and that's a tragedy he just can't shake.

Nathan and Denise Leuthold built their family on faith, but suddenly one of them was dead and the other was under suspicion. It's a story that stays with Andrea Canning, both because of what happened and when it happened: Valentine's Day.

When a novelist's wife is found dead at the bottom of the stairs, investigators wonder if it is an accident or murder; Dennis Murphy interviews main suspect Michael Peterson and returns to the case with insight only he can share.

Eduardo Valseca is taken hostage in an orchestrated abduction; Keith Morrison reflects on the family he spent years following; what happened to them might have destroyed many, but not the Valsecas.

For more than 30 years, Ohio investigators have searched for answers in the murder of 10-year-old Amy Mihaljevic; the case details still haunt Josh Mankiewicz and investigators, who ask for help in solving the crime.

An advocate for missing and murdered Indigenous women searches for answers in the disappearance of her niece and exposes cracks in law enforcement. Andrea Canning looks back on this important story, one that became her passion project.

A double homicide in upstate New York leads detectives on a cross-country investigation; Dennis Murphy reflects on a story full of twists and turns, including the surprising suspect at the center.

The children of an Oklahoma pastor survive the robbery that took their parents' lives; it's a story Keith Morrison still can't forget, and one where the very best and worst of humanity are both on full display.

When a popular graduate student is shot dead in Durham, NC, detectives uncover a deadly love triangle; it takes a lot to surprise correspondent Josh Mankiewicz, but the claims are shocking.

It's a mystery that defies easy answers, and "Dateline" has been following it for more than a decade; Steven Avery and his teenage nephew were convicted of killing Teresa Halbach; now, Andrea Canning shares her insight into the controversial case.

When an Iowa woman is attacked while home alone with her three children, the confrontation turns deadly; Dennis Murphy examines one of the most sophisticated criminal plots of his "Dateline" career.

After a young woman's body is discovered at a trash facility, a detective promises justice and comes face-to-face with a serial killer; Keith Morrison revisits the case.

A woman finds her father, a former FBI agent, murdered at his house; after digging into his past, police suspect the killer might be close to home; for Josh Mankiewicz, the toxic marriage at the heart of this case makes it unforgettable.

When a Kansas prisoner escapes in a van driven by a volunteer, investigators scramble to track down the pair; Andrea Canning likens this story to a bunch of Hollywood blockbusters rolled into one, but it's as real as it gets.

The heir to a legendary hotel is brutally murdered, and detectives learn he had no shortage of enemies; Dennis Murphy takes a fresh look at this extraordinary investigation, a hunt for a killer he calls the most ruthless he's ever seen.

Debra Newell thinks she found Mr. Right, but her daughters sense something wrong about John Meehan; their search for answers exposes a dangerous con man and deceit that runs as deep as any Keith Morrison has covered.

A Mediterranean cruise meant to rekindle the love between a woman and her ex-husband leads to her disappearance; the investigation reveals secret recordings and an undercover hitman; Josh Mankiewicz reflects on the cold-blooded crime.

Debbie Kelly and Lars Itzo make their marriage of opposites work; when Debbie is killed, there is no question about who shot her, yet the explanation of why is one of the most confounding Andrea Canning has heard.

Newlywed Dalia Dippolito comes home from the gym to find out her husband has been killed; in a case Dennis Murphy will never forget, almost nothing is as it seems; he explores whether Dalia was a pawn in a hoax gone wrong or simply diabolical.

They were two beautiful families living out their dreams, but gunshots in a parking lot revealed an ugly truth. Detectives uncovered three lives tangled in a love triangle. Keith Morrison finds the tale of deceit and betrayal unforgettable.

For a group of stage actors, life seemed to be imitating art in the worst way when a college student was killed.

Andrea Canning looks back on the royal who has fascinated her since childhood, Princess Diana. She explores Diana's real story, including a look at her troubled marriage, turbulent life and the investigation into her death.

A couple takes a scuba-diving trip to the British Virgin Islands. On their last dive, one of them surfaces but the other does not. Police quickly suspect the drowning was no accident. Now Dennis Murphy gives this unforgettable story a second look.