BBC iPlayer

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.

An emotional thrill ride through the day-to-day chaos of the city's newest state-of-the-art trauma center and into the lives of the courageous doctors, nurses and staff who hold it all together. This is one of those days.

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.

Mark Scout leads a team at Lumon Industries, whose employees have undergone a severance procedure, which surgically divides their memories between their work and personal lives. This daring experiment in "work-life balance" is called into question as Mark finds himself at the center of an unraveling mystery that will force him to confront the true nature of his work… and of himself.

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.