After a US agent working at a top secret missile test site mysteriously dies, spy chief Harding (Howard St John) suspects there is a foreign spy ring after US secrets. British agent Langton (Ron Randell) begins to work at the test site to seek out the spies.
The base secretary Karen (Amanda Blake) comes under suspicion, especially as she has regular meetings with Dr Gilbert (Lewis Martin)...
This is a good film with some interesting scenes, some spy drama brutality and an exploration of the art of international espionage. The spies' identities are kept ambiguous, quite possibly neo-Nazis instead of the Soviets. The post-war paranoia is high, the film is also interesting in using Karen's concentration camp survival as a plot point.
