American and English intelligence services are aware that three atomic scientists are to meet in Tangier, pool their secrets, and sell the results to the Rusky Communists. American secret agent Steve Gordon (George Brent),posing as a black-market operator, has established contact with Kozad (Bert Freed), wealthy head of the Communist (because he is not in Russia) and his three henchmen Korvich (Shepard Menken), Rosnov (Richard Karlan, and Ivan (Michael Ross, billed as Mike Ross.