A daring gang, working with military precision, steals an Army tank and kills a good friend of Dave Barrett, who sets out in pursuit, unaware the tank is to be used in an epochal jailbreak.

Dave Barrett is thrown into a chain-gang prison and singled out for special mistreatment after his search for a missing prisoner threatens the warden's corrupt regime. Joining forces with a black prisoner, Simon, Barrett lays plans to escape.

When a ship carrying six murdered men drifts into a harbor, the daughter of one of the victims asks Dave to find the killer.