Life-Line, Robert A. Heinlein's groundbreaking first published story, introduces readers to a provocative concept: the exact prediction of a person's lifespan. When Dr. Hugo Pinero unveils his invention — a machine capable of determining the precise date and time of anyone's death — the world reacts with a mix of fascination, fear, and outrage. Heinlein explores the ethical, social, and economic upheavals that follow this revelation. Insurance companies face ruin, religious leaders question the implications for faith, and individuals must confront the uncomfortable truth about their own mortality. With sharp dialogue, clever twists, and a wry sense of irony, Heinlein transforms a speculative premise into a thoughtful reflection on human nature, freedom, and fate. Though brief, Life-Line contains the seeds of many themes Heinlein would develop throughout his career: the clash between innovation and entrenched interests, the resilience of the individual, and the often unpredictable consequences of scientific progress. A classic of early science fiction, Life-Line remains as engaging and relevant today as when it first appeared in 1939.