Fred Lang, an enemy agent, works as an engineer on a missile base in Los Angeles. He learns that a group of scientists is scheduled to fly to Cape Canaveral and is ordered to place a bomb on the plane.

Commander Matson enters Czechoslovakia disguised as an art dealer, part of a plan to get atomic scientist Andrew Fleming out of the country. Tension mounts as the time of Fleming's trial nears and Matson has to call upon a group of Czech resistance fighters for help.