A convicted man, Vince Ryker, manages to escape from a labor camp with what he thinks is a container of heroin, unaware it’s actually a lethal radioactive powder. The container is a part of a hospital shipment that went missing and is filled with Cobalt-60, a material that can cause devastating harm if spread. Ryker's ignorance of the true contents fuels his carelessness, endangering anyone he comes into contact with as he heads to the city, intending to sell what he believes are drugs.

Meanwhile, the authorities are in a frantic rush to locate Ryker and the stolen container before it leads to a catastrophic event. They race against the clock, aware of the deadly consequences if the substance is dispersed among the unsuspecting public. A lead detective is tasked with the urgent manhunt, knowing full well the invisible threat that looms. The tension escalates as the city remains oblivious to the danger, and the chase intensifies to prevent a possible disaster.