Season 4

Over three days, five college students are brutally murdered in Gainesville, Florida. As investigators search for the serial killer, panic fills the usually sunny city.

Five college students are found brutally murdered in Gainesville, Florida. However, it takes investigators months - and the discovery of a campsite, a screwdriver and an audiotape - before they can identify who the serial killer was.

On June 5th, 2002, Elizabeth Smart is kidnapped from her Salt Lake City home, snatched from her bed at knifepoint by a mysterious man in the middle of the night. To the public it seemed as if she had vanished into thin air, but she was actually taken by 48-year-old Brian David Mitchell. A look at the unbelievable nine month saga with its unforeseeable twists and turns, a police investigation that went sideways, and a family fighting to keep hope alive.

For nine months, in 2002, 14-year-old Elizabeth Smart is the most famous missing child in America. Kidnapped by Brian David Mitchell, she was forced up into a hiding spot in the mountains behind her home, assaulted and forced to be his second "wife." Following the harrowing of her nine month ordeal, including the multiple trips they took to Salt Lake City where she was hidden in plain sight. And the unbelievable end, one of the most incredible kidnapping recoveries in U.S. history.

On October 25, 1994, Susan Smith reports that a carjacker has abducted her two young sons, Michael and Alexander. This report sets off a nationwide search for the boys. While the world waits for news about the boys, investigators deliver shocking news.

For nine days, the nation waits for news as to the whereabouts of missing 3-year-Michael and 14-month-old Alex Smith. Then, there's a shocking break in the case. The boys' father, David, shares his heartbreaking story.

On Oct. 28, 2007, 23-year-old Stacy Peterson, the wife of veteran police sergeant Drew Peterson, goes missing. As police launch an intensive search to find Stacy, the case raises shocking new questions about her husband.

Actor-musician David Cassidy ("The Partridge Family") experiences the pressures of fame as a teen idol in the 1970s. In the end, his death is surrounded by mystery, leaving his family, friends and fans with more questions than answers.

On April 19, 1995, Timothy McVeigh, a 26-year-old U.S. army veteran, detonated a 7,000 pound truck bomb outside the Alfred Murrah Federal Building in downtown Oklahoma City, claiming the lives of 168 innocent people.

In an exclusive prison interview, Timothy McVeigh himself describes how events in his personal life - and in the ever-changing world around him - inspired him to take action against his fellow Americans.