On Sunday July 23, 1967, the 12th Street Riot begins when a celebration is held for black veterans returning home from the Vietnam War. The celebration is taking place at an unlicensed club, and so the police raid the place, making several arrests. The event's attendees are angry and a mobilize themselves into a mob. They throw anything they can get their hands on at the police, spilling out into the street and damaging neighboring businesses. There is looting and the mob set fire to several buildings along the street.
Nobody can seem to break up the violence. There is mass panic and the city seems to be in the grip of an anarchic force that nobody, not the police or the city's elected officials, can break up. Governor George W. Romney sends in the National Guard; the president sends paratroopers into the city to try to help.
On the second day of the riot, a policeman named Philip Krauss pursues a looter who is running away from him. Krauss is told to hold fire but shoots the man anyway. Whilst his superiors decide whether or not the shooting was justified, he remains in post.
Meanwhile, The Dramatics were in Detroit looking for a recording contract; after all, it is the home of Motown, and they have managed to book a music venue where they will play for local record scouts. Because of the rioting, the venue is closed down for everyone's safety, and The Dramatics are told to go home. Their bus is attacked as they try to drive out of the city, and so they decide to split up. Larry Reed, the band's lead singer, and his bodyguard Fred Temple, stay overnight at the Algiers Motel, where they meet Julie Ann Hysell and Karen Malloy. who are at the Algiers with a group of friends. For the moment the motel seems like a safe place to be.
The same cannot be said for the grocery store, where a security guard, Melvin Dismukes, has been hired to protect both the store and the clerks working there. One of Julie Ann's friends, Carl Cooper, is enjoying himself firing blanks from his pistol, hoping to frighten the troops. They have no idea that the bullets he is firing are blanks and mistake the sound for sniper fire. Seeing the muzzle flash briefly they identify the shooter's location as the Algiers Motel, and the National Guard are sent over there to investigate. Police officer Krauss is with them; he shoots and kills Cooper as he tries to escape, planting a knife next to his body to make it look as though this shooting was in self defense.
Everyone in the hotel gathers downstairs. The police line them up and demand to know the identity of the sniper. Krauss grows more abusive and the National Guard disassociate themselves from him and his increasingly uncontrollable behavior but they do not inform their superiors of their concerns.
Krauss picks out suspects at random and conducts mock executions to scare the other guests in the hotel into confessing their knowledge of the sniper. Officer August does not understand the concept of a mock execution and believes that Krauss has ordered him to kill a prisoner; he does so, executing a man named Pollard, who was among Julie Ann's group of friends. Krauss is worried that he is going to get in trouble and allows everyone else to leave, but he shoots Temple when he will not stop jabbering that he has seen a dead body.
Eventually the riot starts to quiet down. Dismukes is identified as the murderer of Pollard by Julie Ann Hysell. Gradually the other police officers confess their involvement, all except for Krauss. When the trial begins, Reed is called to testify about the events that he witnessed that night. He has not really resumed singing since the riots; he has a kind of PTSD that has slowed down his career's trajectory. The judge will not accept the police officers' confessions into evidence - and they are the sum of all the evidence that the state actually has. It does not take long for the jury to dismiss all charges against Dismukes and the officers on trial.
Those acquitted of the murder resumed their lives with varying degrees of success. Dismukes moved to the suburbs, where he lived a safer life and continued working as a security guard. Krauss, August and Paille were never on active duty again, despite being acquitted of all charges. Decades later, a civil court ruled in favor of Pollard's family and the officers were ordered to pay $5,000 in damages to his family. Julie Ann Hysell left Detroit too, married, had children and worked as a hair stylist. Reed never rejoined The Dramatics after the riots, but they did eventually make it in the music business, and still tour to this day.
