A woman vanishes while driving on I-95 in Florida; her divorce leads police one way, then her body is found, suggesting a different more horrible path; another woman reads about the case and has a hunch she knows the killer.

As the cases of a missing cheerleader and a roadside fire converge, police juggle numerous suspects and motives, then a cryptic surveillance video brings the investigation to a shocking conclusion.

When a young woman vanishes from a New Mexico convenience store, two detectives discover tracks in the dirt that may lead to answers; after a second woman disappears, it's a race against time to stop a possible serial killer.

Star student Brittney Gregory, 16, vanishes from Brick Township, N.J., in 2004; police launch an investigation that leads them into a world of dark secrets and dangerous players as they strive to solve her disappearance.

Twenty-eight-year-old U.S. Army veteran Joey Fulgham is shot dead in his bed in May 2003; police have a lot of ground to cover with a large number of suspects, including Joey's wife, her jealous boyfriend and even her protective teenage brother.

After an Arkansas outdoorsman disappears, authorities wade through accusations and rumors in their hunt for the missing man; as they zero in on a suspect and the body count rises, detectives rush to capture the killer before it's too late.

After helping a friend fix his computer, 18-year-old tech prodigy Sam Poss takes off on foot and never returns home.

In 2006, a young woman and her baby are found murdered at home; detectives discover a complicated romance, a revelation and evidence to make an arrest.