What? What does it take to be a detective in one of America’s toughest cities? Follow one homicide unit as Detroit’s finest reveal the crisis and revelation, heartbreak and heroism that characterize these inner city cops in this series shot entirely in Detroit, Michigan, which premieres Tuesday, September 21, on the ABC Television Network. There’s the damaged but driven Detective Louis Fitch, a wily homicide vet who is the most respected — and most misunderstood — man in the division;