A wealthy Hollywood mogul, obsessed with the prospect of his own mortality, enlists his physician to uncover the secrets of extreme longevity. The protagonist, Jo Stoyte, commands immense resources but remains trapped by a profound fear of death, leading him to fund research that promises to extend his life indefinitely. His physician, Dr. Obispo, operates with a cynical detachment, viewing the quest for immortality as a scientific puzzle rather than a moral endeavor. The narrative unfolds through a blend of sharp social observation and philosophical inquiry, tracking the characters as they navigate the artifice of the California elite in pursuit of a biological impossibility.

Readers and critics frequently highlight the sharp contrast between the book's comedic Hollywood setting and its grim, philosophical conclusion. Discussion often centers on Huxley's ability to weave dense intellectual arguments regarding the nature of time and human vanity into a narrative that remains engagingly cynical. Many observers note that the pacing shifts significantly as the story moves from social satire to a more somber, reflective tone in the latter half. The work is often cited for its biting wit and the author's capacity to dismantle the superficiality of his characters through precise, clinical prose. Readers generally appreciate the balance between the plot's absurdity and the underlying gravity of the themes presented.