Exile Express
Anna Sten plays Nadine Nikolas, a Russian emigrant to the United States who is diligently studying for her citizenship qualification exam and employed as a laboratory assistant for a research chemist, Dr. Hite (Harry Davenport) who has developed a sort of pesticide that can also be a horribly lethal weapon. Some foreign power wants to get the formula, and the authorities suspect that Nadine is involved in the plot. She isn't, but she's ordered deported anyway.