Captain Vinka Kovelenko defects from Russia, but not for political reasons. She defects because she feels discriminated against as a woman. Captain Chuck Lockwood gets the order to show her the bright side of capitalism, while she tries to convince him of the superority of communism. Naturaly, they fall in love, but there's still the KGB, which doesn't like the idea of having a defected Russian officer running around in London.
—Stephan Eichenberg

After leaving the British Secret Service, David Somers (played by Trevor Howard) finds work cataloging butterflies at the country house of Nicholas and Jess Fenton. After the murder of a local gamekeeper, suspicion (wrongfully) falls on their niece, Sophie Malraux (Jean Simmons). Somers helps Sophie to escape arrest and they go on the run together. After a cross-country chase they arrive at a coastal city with the intention of leaving the country by ship. All's well that ends well after the true identity of the murderer is revealed.

When Newman decides she doesn't want to be burdened with children, she decides to take the pill--which, as we all know from those ubiquitous posters of the 1960s, was a "No No" so far as the Pope was concerned.