Two women are murdered in the same Arlington, Texas apartment complex, and police are stumped. Years later, evidence from two subsequent rapes provides a breakthrough. Andrea Canning reports.

A young Fairfield, Ohio, woman, 21-year-old Katelyn Markham, vanishes one summer night in 2011, prompting her community to conduct a massive search. When her skeletal remains are found in Indiana two years later, investigators question her friends and family to uncover her killer, but it takes 12 years and a detective with dogged determination.

In Humble, Texas, a frantic 911 caller, 16-year-old Keri Murphy, reports hearing her mother's screams after an intruder entered their home. When first responders arrive, they find Mary Ann Murphy dead after receiving more than 70 stab wounds. What happened on that dark summer night?

In Marietta, Georgia, a woman's murder shines a light on an unsolved mystery from years earlier. As the connection between the two cases becomes clear, a long-hidden truth surfaces. Could a master manipulator be behind both crimes? Andrea Canning reports.

Millionaire entrepreneur Lance Herndon is found bludgeoned to death in his Atlanta home. The search for his killer reveals no shortage of suspects or secrets.