When a blackout strikes the city during a heat wave, Sully prophetically warns the more optimistic Ty that trouble in the streets will swiftly ensue. After Carlos leaves the ambulance running to keep the bus cool while he and Doc are on calls, the engine catches fire and the ambulance is destroyed. A wealthy old man confined to his bed by illness offers them a large amount of money to stay with him until his daughter arrives. Doc insists that they leave to treat others more in need over the protests of Carlos. Bosco arrests a young man, Latrell Griffith, and faces a difficult decision when an immigrant shop owner shoots and wounds a teenage shoplifter. After Latrell uses his training as a medic to save the boy, a riot breaks out and Bosco, Latrell and the shoplifter barely escape. Nightfall brings more unrest as the nervous cops try to keep the peace. Faith and Fred are stuck in a elevator when the power goes out. Faith tries to calm Fred's mounting anxiety about being trapped, and is left helpless when Fred suffers a heart attack.