They were bright young women out for a little fun with their friends. Kenya Monge and Lydia Tillman didn't know each other but they would be forever related, both falling prey to a smooth-talking stranger with a terrifying secret.

It began with a young mom abducted at gunpoint. Her family and veteran investigators spent desperate days trying to find out where she was but they never could have guessed WHO had her and WHY.

What happened that September night when romance turned to danger? Something went terribly wrong and a woman slipped over the edge of a cliff. Did she fall by accident or was she pushed? It would take almost 20 years to find answers.

For investigators, motive can be the hardest thing to find. This crime took place in Florida but detectives didn't discover a motive for murder until they looked into a tropical island thousands of miles away, where a festering grudge was born.

It started with a frightening horror flick from the '80s. Then decades later, it was happening for real. Four people were dead and investigators believed they were chasing a serial killer. Could this old movie hold the key to solving these cases?

Young nursing student Michelle Le had disappeared. Something drew her out to her car. As her loved ones launched a very public effort to find Michelle, investigators began their own methodical search. Was she missing or murdered?

It was Easter Sunday. The Stock family celebrated at home. Hours later, gunshots turned their farmhouse into a house of horrors. There was an arrest but one tiny clue didn't fit. This case was far from being solved.

Dr. Mark Weinberger was a successful surgeon hiding a secret from his medical staff and from his adoring wife. There was a malpractice suit and a death. Then the doctor vanished, sparking an international manhunt and a family's fight for justice.

Kate Waring and Heather Camp meet on a train from Washington DC to Charleston SC. Kate suffered from depression due to molestation in her younger years. While turning her life around she was betrayed by Heather, a long time con-artist.

Detectives often hit dead ends that can stop them cold but, for one young detective, dead ends were just another place to start. She'd beaten the odds in her own life. Now, she was determined to beat them on the job using her head and her heart.

Was he missing or was he hiding? On the surface, it didn't make sense: 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 love triangle leads to a murder investigation when a beauty queen, a wife, and a guitarist become entangled in a scandal that causes one Florida man to use a passing hurricane as cover for him to hide from his past mistakes.

It was a plot straight out of an Alfred Hitchcock film. A woman peers into a neighbor's yard and catches a glimpse of something unsettling. What she saw and what she did set a chain of events in motion that would divide a family and a jury.

Celebrity dog trainer Mark Stover and his wife, Linda, built a thriving business and a beautiful home but their dream life didn't last. An affair led to a bitter divorce. Then Mark vanished in a mystery with the makings of a Hollywood thriller.