Sam discovers that his mother in 1973 owes money to a gangster who has a very cozy relationship with the precinct. But Sam is the only person who isn't willing to take the payoffs and look the other way.
Sam partners up with his future police mentor in 1973 to find a Puerto Rican man accused of throwing a black girl off the roof of a building--a case that has the black community up in arms and demanding retribution.
The precinct goes into lockdown when a councilman is shot and killed in the station. But before he is killed, the councilman tells Sam that he is from 2009 and that he has found a way to get back home.