A man desperate to leave South America books passage on a freighter, and learns that the captain has made plans to force a scientist to participate in a mission of destruction.
A group of communist spies plan to blow up an essential commercial artery, the Panama Canal. To this end, they have kidnapped a nuclear scientist and are traveling by steamship to the coast of South America. Luckily for western civilization, the hard-nosed ship's captain, played by Barton MacLane, has other ideas.
