Starting over isn't easy, especially for John Nolan who, after a life-altering incident, is pursuing his dream of joining the LAPD. As their oldest rookie, he's met with skepticism from those who see him as just a walking midlife crisis.

A riveting police drama about the men and women of the Chicago Police Department's District 21 who put it all on the line to serve and protect their community. District 21 is made up of two distinctly different groups: the uniformed cops who patrol the beat and go head-to-head with the city's street crimes and the Intelligence Unit that combats the city's major offenses - organized crime, drug trafficking, high profile murders and beyond.

A mysterious "time master" from the future unites an unlikely group of superheroes and villains to save the world from a powerful evil.