The Time Machine by H. G. Wells

A Victorian-era scientist invents a machine that allows him to travel through time. He first journeys to the year 802,701 A.D., where he encounters the Eloi, a society of small, elegant, childlike adults who live in harmony but lack curiosity and drive. He later discovers the Morlocks, a nocturnal, subterranean species who prey on the Eloi. After rescuing an Eloi named Weena, the protagonist loses his time machine and must devise a plan to recover it and return to his own time, all while exploring the social and evolutionary implications of the two distinct societies.

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