Dateline: Secrets Uncovered

A notorious serial killer, nicknamed Hannibal, murders several people while working as a confidential informant for the FBI.

Chilling details come to light in an alleged murder-for-hire plot targeting a former NYC police officer's husband; the officer's ex-boyfriend and other insiders close to the case speak out in their first TV interviews.

A romantic interlude on a September night turns tragic when a woman slips over the edge of a cliff and falls to her death; authorities ask whether she fell or was pushed, and it will take 20 years to find the answers.

A young mom's abduction at gunpoint leads her family and veteran investigators to spend desperate days trying to find out where she was taken, but the suspect and motive both come as a surprise.

Decades after Susan Smith confesses to drowning her two small sons in South Carolina, she advocates for parole; her ex-husband speaks out, arguing that Susan should remain behind bars for the notorious murder of their children.

The investigation into the mysterious disappearance of a Canadian man sparks an international manhunt for an elusive killer with multiple false identities.

A week before a wealthy banker's divorce was set to reach a settlement, an ex-con says he was hired to murder someone in the family.

New details in the murder case of a professional cyclist; interview with the plastic surgeon who convicted murderer sought out while on the run.

A massive manhunt ensues after Lois Riess murders her husband in Minnesota and flees to Florida, where she kills and steals the identity of a woman she had just met.

The discovery of a young woman's body in an abandoned building in rural Texas sparks a multi-state investigation lasting nearly two decades.

A quiet North Dakota college town is left in fear after student Mindy Morgenstern is found murdered in her off-campus apartment.

Four years after a 28-year-old dies after hosting a New Year's Eve party, a jury must decide if it was suicide or murder.

A small Ohio town is left in shock after a local coal miner is found fatally shot in his basement; as investigators dig into his personal life, a secret affair reveals a surprising suspect.

After four people turn up dead, investigators chase a serial killer who may be reenacting scenes from a horror movie released in the 1980s.

She was beautiful, trusting and troubled; the young woman from a prominent family was just turning it around and realizing her promise; then she vanished; when the police seemed unable to find her, her family hatched a plan to solve the mystery.

When high school student Megan Nichols vanishes from her Illinois home, her mother finds a note saying that she ran away; a grisly discovery made three years later changes the course of the investigation.

Was he missing or was he hiding; he had a wife, a good job, a daughter he loved; investigators were told he also had a secret and they went on an undercover mission to find the truth.

A teenager's life is turned upside down by a shocking discovery as what seems like a fatal accident reveals itself to be something much more disturbing.

When Courtney Copeland is shot and killed, his mother investigates whether police detectives did enough to try to solve the case.

Russel Douglas is a troubled father hoping for a fresh start when he is found shot dead in his car; the investigation turns up few clues until an anonymous tipster sends detectives on an international manhunt to unravel a mystery.

Judy Carlson lived in a painful limbo; her son disappeared without a trace; years went by and she may never have known his fate if not for a rookie detective's dogged work, but to solve this cold case, the investigator also need the help of a killer.

Jack Jessee was a family man who didn't seem to have an enemy in the world, up until the night he was killed; the case goes cold but a relentless detective is determined to catch Jack's killer.

When deadly gunfire erupts in an Austin, Texas home in the middle of the night, detectives wonder if the homeowners' jewelry business is a possible motive; an investigation uncovers a suspect no one saw coming.

Larry McNabney has a thriving career and a wife he adores, but then vanishes; at the center of the twisted mystery, three lives tangle together in a love triangle, including one who hides a secret identity.

Friends of accused murderer Robert Durst talk about his arrest in New Orleans and his previous whereabouts over 30 years.

Michelle Young was married to her college sweetheart and pregnant with their second child when she was murdered; in the search for her killer, detectives uncovered a marriage riddled with secrets but cracking this complicated case took years.

The neighbors enjoy mixing business with pleasure then a murder makes them face the reality that a killer is in their midst.

Steven B. Williams, a DJ with a golden voice, vanishes in a mystery that stretches from California to Montana; the clue to it all is wrapped in a napkin, tucked in a cabinet and hidden in a library.

Detectives often hit dead ends, but one young detective sees dead ends as starting points; she's beaten the odds in her own life, and, now, she's determined to beat them on the job using her head and her heart.

In a plot straight out of an Alfred Hitchcock film, a woman peers into a neighbor's yard and catches a glimpse of something unsettling; she sets into motion a chain of events that will divide a family and a jury.