Hitchcock's first film in colour, and his first as producer/director, remains one of the most extraordinary technical achievements m the history of the cinema. The entire action takes place within a single set, and the 81 minutes' screen time coincides with dramatic time .

Hitchcock covered the action in ten minute takes (the maximum running time of the camera's film magazine), and concealed the edit points between each ten minute segment so that the film would appear to the audience as proceeding throughout its length without a single cut.

This technique placed unprecedented strain upon cast and crew, especially as the frequent camera moves demanded faultless precision, strong nerves and sustained effort from everyone on the team.

The setting is late afternoon in a Manhattan apartment shared by two young men Their studies have prompted them to prove to themselves that they are superior beings, able—and therefore entitled—to disregard the rules of society. They murder a fellow student and place the corpse in a chest in plain view of his relatives and friends whom they have invited to tea.

However, the thrill of the situation is disappointing,these ordinary people are not a real challenge. The killers are put on their mettle by the arrival of the teacher whose speculation triggered their action. They perceive in him an authority which creates a desperately contradictory response they want him to recognize their "superiority" and admire what they have done.

But they also fear him, he, too, may be superior (more superior than they?), he may see through the game they are playing, perhaps disapprove, and become the agent of retribution. If they are found out, will that prove they are not superior'. As the afternoon turns to evening the tension grows the name of the game is no longer thrills but survival.