While testing a new fuel aboard an experimental space craft, Col. Steve Austin experiences difficulties while preparing to land and is pulled off course to splash down near a remote island in the Pacific. There, he attempts to contact Oscar at OSI to inform him of his whereabouts, but when another government agent shows up and identifies himself as Oscar's replacement, the Colonel is shocked to learn that 6 years have supposedly passed, Oscar is dead and he has been declared a traitor after supposedly defecting to the Soviet Union

Steve and Oscar learn that a foreign diplomat is using the probe for the purpose of blackmail: the government must turn over two nuclear warheads to him or a U.S. city will be devastated by the probe. Steve must try and stop the probe.