Lewis and Falsone, joined by Stivers, get the case of a woman almost beaten to death and left in an alley. Georgia Rae Mahoney tells Kellerman she has video of Luther's shooting. Frank anxiously awaits the birth of his child, but Mary is unruffled.
An armed robbery at a family Vietnamese restaurant leaves five dead, sparing only two teenagers in the kitchen who implicate an off-duty Baltimore cop. Falsone confronts Kellerman and accuses him of executing Luther Mahoney.
John Lange (Vincent D'Onofrio) becomes pinned between a subway train and the station platform. The Baltimore homicide department is called to investigate whether a crime has been committed or whether the circumstances Mr. Lange finds himself in is the result of a terrible accident.
An angry driver cuts off a state-owned truck, is rammed from behind and rearends a parked semi. Result? Two deaths and a paralyzed passenger, a lawsuit against the state, and pressure on the ME to alter blood alcohol results.
Pembleton and Falsone investigate the mauling of an elderly man, in his own house, by three dogs belonging to his grandson. At the Waterfront, Bayliss, Munch, Gharty, and Ballard share stories of "goofy cases, senseless killings, senseless suspects."
Pembleton and Bayliss investigate the death of a cancer patient when a relative insists the hospice doctor killed him in a "mercy killing." Stivers and Falsone investigate the murder of a 12-year-old girl outside a pizza shop on her way to school.
Bayliss is still having nightmares about the Adena Watson case, so Gee is reluctant to assign the case of another girl, murdered in 1932, to him. Therefore, Falsone is assigned the "oldest unsolved slaying still officially on the books."
Bayliss and Pembleton are handed "the mother of all red-balls," the stabbing of a judge on the sidewalk in broad daylight. It doesn't take them long to connect Georgia Rae Mahoney's feckless nephew to the murder. But unlike their previous contacts with him, he doesn't go easily this time.
The Homicide Unit takes down the remaining Mahoney organization, but not without collateral damage. Stivers tells Gee that Luther Mahoney's shooting is the reason for all the carnage in the past 24 hours.