In the future year of 1950, the world has been fundamentally reshaped by a global pandemic known as "masculitis," a disease that mysteriously targeted and eradicated every male over the age of fourteen. The story follows Elmer Smith, a man who, after being rejected by his sweetheart in 1940, retreated to a redwood forest and unknowingly became the last fertile male on the planet. Upon his discovery by a group of female gangsters, Elmer is thrust into a world where traditional gender hierarchies have been completely inverted, making him the most valuable commodity on Earth.

The film depicts a matriarchal United States where women have assumed all roles formerly held by men, from street sweepers to high-ranking government officials. The societal dynamic is one of orderly but humorously exaggerated female dominance, reflecting the era's anxieties following the passage of the 19th Amendment. Earth is shown as a functional, thriving society despite the near-extinction of the male sex, with the political center of power residing in a female-led Washington D.C., where "Senatoresses" engage in physical combat to settle legislative disputes over Elmer's custody.

The film’s predictions offer a satirical look at 20th-century social progress. It successfully anticipated a female presidency and the rise of women in scientific and political leadership, though it framed these as absurdities caused by necessity rather than natural evolution. While the "masculitis" plague remains a fantastical trope, the film's depiction of a world where women manage global infrastructure and commerce without male intervention served as a provocative thought experiment for 1924 audiences. Interestingly, the film correctly predicted that social vices like alcohol consumption (Prohibition) would remain a point of legislative contention well into the mid-century.