A high-ranking scientist at a major company is part of a Communist spy ring. He is about to turn over notes from a top-secret project. Then he discovers his wife has left home. That's a blow to the ego of the scientist, and he goes off looking for her. Meanwhile, the FBI has already arrested one of the scientist's confederates. Now both the bureau, led by Erskine and Colby, and the Communist agents are in a race to reach the scientist first.