Jacques Duval devises a fiendishly clever method of murdering his wife. Doping her up with sleeping tablets, Duval places his wife in a sealed room, then opens all the gas jets. While the police identify the body, Duval remains hidden in the room, breathing through a snorkel, then makes his escape when the authorities leave. Only one flaw in this perfect crime: Duval’s stepdaughter (Mandy Miller) is the suspicious type.

A wounded criminal and his dying partner take refuge at a beachfront castle. The owners of the castle, a meek Englishman and his willful French wife, are initially the unwilling hosts to the criminals. Quickly, however, the relationships between the criminal, the wife, and the Englishman begin to shift in humorous and bizarre fashion.

Quatermass is the director of an important scientific base, where he builds nuclear rockets for the colonization of the Moon. A strange fall of meteorites in a nearby village leads to the discovery of a huge base under a strict military control, officially a factory of artificial food. Quatermass reveals that the factory is actually breeding alien creatures.