A turn-of-the-century inventor sends himself into the future to save humanity.

Responding to an invitation issued five days earlier, five gentlemen meet at the London residence of their mutual friend, scientist George, who, having arrived late and disheveled, recounts the last five days, beginning with the group's 31 December 1899 meeting: George explains that he has been working for two years to prove the possibility of movement within the fourth dimension, time, by creating a time machine to carry man into the future or past. When George unveils a miniature version of the machine, makes it disappear "into the future" with the switch of a lever and then insists that he, too, will travel into the future, his friends suggest he contribute to the war effort instead of dabbling in tricks. As the others turn to leave, one of the men, David Filby, asks George why he is preoccupied with time. George replies that he is discouraged by human behavior and the proliferation of weapons and asks his friend to return to the house with the others for dinner on 5 January. Returning to his laboratory alone, George seats himself in a full-size version of the time machine, a sleigh powered by a large disc at the rear, and a Victorian chair and a control panel at the helm. As George pushes the main lever forward, a display counter clocks his movement in time. At first advancing only a few hours, George can see the flowers bloom and die within seconds. Pushing ahead, George notices the mannequin in a shop window across the street change styles drastically over each passing year. When his house windows suddenly become boarded up, George stops the machine in 1917 to find a man resembling David on the sidewalk nearby. After the man, James Filby, explains that George must be mistaking him for his father David, who died in the war, George inquires about the "inventor" who lived in the house. James informs him that after the inventor disappeared, David, as executor of the inventor's estate, refused to liquidate the house, certain that the owner would come back. Returning to his house, George removes the boards over his laboratory windows and speeds ahead to 1940, stopping his journey when he feels a large bomb explode in the neighborhood. Realizing that another war is taking place, George continues traveling until 1966. The time machine is now in the middle of a park while sirens sound and all the town's citizens, including an elderly James, scurry to an atomic bomb shelter. Although James begs him to come to the shelter, George remains behind and finds that his sundial has been designated as a park monument to acknowledge David's dedication to his friend George. Suddenly, as an atomic blast destroys the town and molten lava flows through the streets, George rushes to the time machine and throttles ahead. Encased in the hardened lava, George travels through centuries of darkness until the rock finally wears away to reveal a lush and bountiful landscape in the year 802,701. Finding himself outside the large metal door of a temple, George assumes that if man still exists, he has conquered the elements. Drawn by the noise of humans, George walks to a river where several dozen blonde, docile young men and women known as Eloi leisurely bask in the sun. When the others fail to help a drowning woman, George rushes to save her, but finds no one acknowledges his self-sacrifice, not even the victim, Weena. Joining them for dinner, George questions the group about their apathy. The small, delicate Eloi remark that they do not value life nor do they read, write or have any governing laws. When he finds that the last human books have turned to dust, an incensed George reprimands the Eloi for disrespecting the sacrifices of generations before them and returns to the temple to leave, but Weena tells him the machine has been dragged behind the metal door by the Moorlocks, who reside in caves and provide the Eloi with food and clothing. George apologizes for his angry outburst and expresses his hope that he might reawaken the Eloi's spirit of self-sacrifice and scientific inquiry. Later, when they hear the sound of the Moorlocks' machines, Weena explains that the Eloi know about life underground through the rings, which when spun, recite a brief history of the earth. George soon learns how the human race divided itself into the master race of Moorlocks and the Eloi, whom the Moorlocks conquered and enslaved. The next day, when sirens sound, all the Eloi walk in a trance-like state toward the metal door, which opens and takes in several dozen men and women, including Weena. George then runs to a concrete well, where he and several remaining Eloi climb down into the caves, which are covered in human remains, evidence of the Moorlocks' cannibalism. When he finds the Eloi being herded like cattle, George tries to overtake several Moorlocks by wielding his torch in front of the fire-fearing, half-human, half-ape creatures. As a brawl begins, several Eloi, following George's example, use their fists to fight the creatures. Freeing the captured Eloi, George and the group scramble out of a well entrance, throwing blazing torches and dried wood into the pit to cause an explosion, which collapses the caves and kills the Moorlocks. George then tells the Eloi that with their life of leisure over, they must learn to work for themselves. Despite lamenting that he feels trapped in their world, George reveals to Weena that she is his only love. Suddenly, the temple door opens and the last Moorlocks attack George, who clambers into the time machine, pulls back on the lever and returns through the centuries to 5 January 1900. Back at the dinner table, George shows his London friends an exotic flower from Weena as proof of his travels, but the other gentlemen have no faith in George's story and leave. Still concerned for George's health, David returns to the house within minutes, but finds both George and the machine gone when he reaches the laboratory. Spotting tracks in the snow, David deduces that the Moorlocks moved the machine, forcing George to drag it into the laboratory upon his return. When housekeeper Mrs. Watchett asks him if George might return someday, David sagely reminds her that George "has all the time in the world."