City of Fear is a 1959 American film noir directed by Irving Lerner.
Vince, an escaped convict from San Quentin headed for Los Angeles, has a canister in his possession that he thinks has heroin inside of it.
It does not; instead, it contains Cobalt-60, a dangerous nuclear substance with enough radiation to kill most of the population of Los Angeles.
As continued exposure to the element is slowly killing Vince, authorities move to capture him and the canister.
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