Primal Instinct

A documentary series chronicling divorces that turned deadly. Brian Russell, who analyze each couple to better understand how the marriage turned from flawed to fatal. .

A look at the seven murders that rocked the mountain region of Fremont County.

Like trying to decipher the value of a book without ever opening it, judging a person by his or her outward appearance can be a mistake. Someone may look perfect on the outside, but even the most kind-hearted soul has a dark side looming. "Diabolical" is a docuseries that delves into theminds of murderers, asking a simple question: "Why did they do it?" The acts were committed with extreme premeditation -- many were months or even years in the making. Tension builds in each episode as law enforcement taps into the methods of devious masterminds, aided by insights from forensic psychologists and psychiatrists as well as criminal profilers.

The tales of mysterious murders that rocked small-town America. Each hour brings you a new murder mystery and a new look into the evil that can lurk in the heart and soul of a tight-knit community. Interviews with investigators, prosecutors, family members and neighbors piece together the twisting tale of a classic whodunit.

When Donna Jean Awcock failed to return home after babysitting in October 1983, her devastated family had no idea what could have happened. Although her remains were found just one day later in an area not far from where she was babysitting, no arrest has ever been made in connection with the 17-year-old's sexual assault and murder. Thirty years later, Mike Arntfield and his squad are re-examining the case with fresh eyes in their quest to end the family's nightmare. What's shocking is the number of people who could have committed this evil deed.

Stories behind the shocking crimes caught on camera that gain viral fame are featured.