20/20 - Season 5 / Year 2015

Tracker features lone-wolf survivalist Colter Shaw, who roams the country as a "reward seeker," using his expert tracking skills to help private citizens and law enforcement to solve all manner of mysteries while contending with his own fractured family.

Karl Alberg moves to a quiet coastal town to soothe a psyche that has been battered by big-city police work. But this gentle paradise has more than its share of secrets, and Karl will need to call upon all the skills that made him a world-class detective in solving the murders that, even in this seemingly idyllic setting, continue to wash up on his shore.

No job is more stressful, dangerous or exhilarating than those of the Firefighters, Rescue Squad and Paramedics of Chicago Firehouse 51. These are the courageous men and women who forge headfirst into danger when everyone else is running the other way and whose actions make the difference between life and death. These are their stories.

Sheriff Country focuses on straight-shooting sheriff Mickey Fox, the stepsister of Cal Fire's division chief Sharon Leone, who investigates criminal activity as she patrols the streets of small-town Edgewater while contending with her ex-con father, Wes, who is an off-the-grid marijuana grower, and a mysterious incident involving her wayward daughter.

In the criminal justice system, sexually-based offenses are considered especially heinous. In New York City, the dedicated detectives who investigate these vicious felonies are members of an elite squad known as the Special Victims Unit. These are their stories.