Z.P.G (Zero Population Growth) is a 1972 film starring Oliver Reed and Geraldine Chapman. As the name suggests, its plot revolves around Population Control, which is announced at the start of the film by the World Federation Council. This version is harsher than most — having children is banned completely for 30 years, and punishable by death. To make up for this, life-like dolls are made to replace them which couples then care for, mimicking the affection, tears, and even illnesses of actual children. The central conflict involves a couple who conceive a child, and the subsequent consequences of this.
- Crapsack World: Along with being controlled by a dictatorial global state, the Earth's atmosphere is so polluted that face masks are required to go outside, most animals (including the domesticated kinds) have gone extinct, most bodies of water were filled in to create more housing for their increased population, despairing old people rot away in retirement homes, people wear monochrome uniform jumpsuits, there are years-long waiting lists just to visit a museum, the only food is indistinguishable goop, and they must watch films of the "excessive" things people ate in the old days before everything collapsed.
- Dystopia: The World Federation, a global state that controls its citizens' lives very tightly, keeping them on a strictly rationed diet, constantly broadcasting propaganda, monitoring public library computers so closely that state security can pull someone in for torture at a moment's notice if they looked up the wrong subjects, using brainwashing, registering existing children, mandating abortion with the push of a button after couples have conceived, and publicly killing those parents (along with their children) who violate the reproduction ban by suffocating them in a plastic sphere lowered by helicopter.
- Good Girls Avoid Abortion: Inverted according to the law of the society in the film, which mandates abortion since reproduction is banned. The central plot comes up when the female protagonist Carole fails to have one and secretly gives birth to a child, making her go on the run with her husband Russ.
- No New Fashions in the Future: Everyone still uses The '70s' styles, even though it's supposed to be sometime after the turn of the 21st century.
- Population Control: The basis of the film's plot. Reproduction is an offense punishable by death.
- 20 Minutes into the Future: The dialogue speaks of the "early 21st century" being the past, and it was filmed in 1972. It may be set in the (former?) UK, given the British Accents of most characters. There was also a "great famine" in the past, according to the State Museum, which led to riots according to an old newspaper, "killer smog" in Los Angeles that left 9,000 dead, and, going by a plaque on the beach in the last scene, all their nuclear missiles were buried in 1978.