Episode 4

District 21 of the Chicago Police Department is made up of two distinctly different groups. There are the uniformed cops who patrol the beat and go head to head with the city's street crimes. And there's the Intelligence Unit, the team that combats the city's major offenses - organized crime, drug trafficking, high profile murders and beyond. These are their stories.

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.

High Country tells the story of detective Andrea Whitford who is transferred to the Victorian High Country, where she is thrust into a baffling mystery of five missing persons who have vanished into the wilderness.

High Potential follows Morgan, a single mom with an exceptional mind, whose unconventional knack for solving crimes leads to an unusual and unstoppable partnership with a by-the-book seasoned detective.

9-1-1 is a fast-paced exploration into the lives and careers of first responders – cops, paramedics, firefighters – the people who put their lives on the line to save others.