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.

Kate Gray struggles with a full-time career as a therapist, raising four young children, past personal traumas, and marriage. She tries to hold it all together, spiralling through the "gray area" of addiction and anxiety.

When a woman trying to outrun her past ends up trapped between a zombie outbreak and warring militia groups, she is caught in a world where some fight for survival but others fight for control.