This premiere episode tells the story of a mother named Dawn and her son Justyn. It chronicles her realization that the child she raised had become someone she no longer recognized—a person capable of a "monstrous" act.

In 1995, three brutal murders span Oregon and California, leaving several families shattered and communities terrified. When police identify Robert Acremant as the killer, his father, Ken, is confronted with the reality that his son is not the man he thought he knew. Ken is then forced into making an agonizing decision no parent should have to make - to call authorities and turn in his own son, knowing it will change both of their lives forever. In the aftermath, Robert never forgave his father, leaving Ken to carry the weight of that choice alone.

Jeannette does everything she can to care for her son, Timmy. It is a struggle, but she thought she was doing a good job. Then, his dark side emerges. He is violent, unpredictable, and dangerous. Despite every effort to help her son, she watches helplessly as he spirals into darkness. Exhausted, overwhelmed, and fearful for her family, she plans something unimaginable for any parent: she wants to kill her own son to save herself and possibly others.

When Tim Jones Sr. thinks of his son, he remembers the boy he raised - bright, capable, and full of promise. But that memory is forever stained by blood. Even though he saw the signs that is son was unraveling and tried numerous times to reach him, nothing could prepare him for the horror to come. When his son, Tim Jones Jr., brutally murders all five of his own children, Tim Sr. is left shattered, forced to confront the unthinkable truth about the boy he raised and the evil he never imagined.

As a single mother having overcome a battle with addiction, it's not easy for Charity Lee to raise her son, Paris, and daughter, Ella. Despite what appears to be a loving family and a sibling bond she could have only hoped for, she could never have foreseen the true monster her 13-year-old son was hiding within.

Cary Buchanan spent years trying to help his son, hoping his anger and instability would pass, but nothing prepares him for his daughter's call: "Mom is dead ... and Matthew did it." But Cary learns that's not all - he might be coming to kill him too.

Sonia Ramirez watches her bright, athletic son begin to change - picking fights, breaking the law, even claiming he sold his soul to the devil. Still, nothing prepares her for the day that darkness costs her not only her son, but her daughter, too.