In 1988, a man is released from jail after a judge deems his murder confession false. For 25 years, a family's hope for justice fades, as the killer walks the streets. But one tenacious detective refuses to let this cold case go.

One night in 1993, in Manhattan Beach, California, an officer is shot and killed during a routine traffic stop. The only witness is a young boy who is too terrified to tell police what he saw.

In 1995, a beloved mother is found raped and murdered in the accounting office where she works. The bloody body of her young daughter is nearby. But as police photograph the scene, they get the shock of their careers.

In 2004, the cat-and-mouse hunt for a serial killer targeting black females antagonizes investigators in Peoria, Ill.

In 1997, in quaint Anne Arundel County, Maryland, a detective inherits a stack of cold cases. As he begins to unravel each one, he uncovers a shocking and gruesome common thread.

When Lovetta Armistead, a beautiful and hardworking single mother in Oak Cliff, Texas, marries a new man, Gary Green, she has no idea the monster she's brought into her home.

In 1995, a desperate mother in Conroe, Texas, learns the hard way that sometimes Satan takes the form of a family friend.

In 2003, a young man in Georgia shoots his father in the head sixteen times. Days later, the body of a nun is found on the side of a Virginia road. The story behind these two crimes haunts those involved to this day.

In 2003 in Burlington, North Carolina, pregnant April Greer vanishes. Her boyfriend says she left him, and her family is worried sick. No one knows that the unbearable truth about what really happened to April is the stuff of nightmares.

When five people vanish in 1993, cops have zero leads; seven years later, someone connected to the case starts to talk.

In 2007 in Bethany, Oklahoma, a young pregnant woman goes missing. Police desperately try to retrace her last steps, and unearth more than just the secrets she harbored.

In 1993, a family is torn apart when a mother in Jacksonville, Florida goes missing. The case stumps detectives, who believe that the truth about what happened to her is locked inside the mind of the missing woman's three-year-old son.

For two years, in Dallas, Texas, surgical patients fall victim to Christopher Duntsch, a monster with a scalpel and a medical degree. Dallas Assistant District Attorney Michelle Shughart isn't sure what to think when she is first approached with the case. Is this medical malpractice? Or an evil man with a scalpel?

For six months in 2014, a serial killer preys upon innocent victims in Los Angeles.

After a Valentine's dance in 1974, 17-year-old Carla Walker is kidnapped by a man with a gun. For 45 years, the case goes unsolved, and no one knows that the person responsible is living uncomfortably close, hiding in plain sight.

In 2011, Mother's Day in Tustin, California, looks a little different this year for high school freshman Tony Gana. His mother, Annamaria Gana, is battling stage 2 breast cancer. She says she's fine, but Tony can tell the medicine and the chemo is taking its toll. Officer Todd Hylton is called to the scene of an alleged shooting. Just moments earlier, the caller told dispatch that his mom shot him

In 2001, in Cortez, Colo., the violent murder of a gay Navajo teenager means two spirits die with him.

In 2016, when a beloved young mother vanishes, her family - desperate for answers - makes a deal with the devil.

In 2019, when a beloved father vanishes, his home appears spotless, but there’s something odd about the flower garden.

In 1980, in Radford, Virginia, college freshman Gina Hall goes out dancing and never returns. Police follow her trail to a mysterious lake house, but where she goes from there is a mystery that has endured for 40 years.

In 2008, a real estate developer finds his glamorous wife Kay Wenal slashed from ear to ear in her Georgia home; with few clues in the case, investigators quickly learn that all is not what it seems in her picture-perfect life. [also shown as S3:E12]

In 1996, in Tulsa, Oklahoma, a young mother is found dead on the side of a rural stretch of highway in an apparent hit-and-run accident. But as the family grieves, the façade begins to crack, and soon the truth seeps out.

In 2000, in South Barrington, Illinois, a rookie cop responds to the scene of what many believe to be the site of an accidental drowning. But for that cop, something about it doesn't sit quite right. It's a hunch that, 10 years later, he still hasn't forgotten.

In 2011, as the manhunt for a dangerous cop killer rages across Athens, Ga., police get a call from the man they are looking for; he's not alone and has hostages, and police fear he wants to go down in a blaze of glory.

In 1995, when a 14-year-old girl in Happy Valley, Washington, goes missing, detectives uncover a grim family secret.