The Bed Sitting Room (1969)

Among the ruins of a London devastated by nuclear war, the survivors ineffectually cling to increasingly meaningless social structures. While radioactivity randomly transforms various people into animals and inanimate objects, an absurd election for prime minister takes place. And the parents of Penelope (Rita Tushingham), a young woman who's been with child for nearly a year and a half, want her to marry a man with a promising future, though the fate of the world itself is rather dim.