It is the late 1750s, and the French and Indian War grips the wild forest frontier of western New York. The French army is attacking Fort William Henry, a British outpost commanded by Colonel Munro. Munro’s daughters Alice and Cora set out from Fort Edward to visit their father, escorted through the dangerous forest by Major Duncan Heyward and guided by an Indian named Magua. Soon they are joined by David Gamut, a singing master and religious follower of Calvinism. Traveling cautiously, the group encounters the white scout Natty Bumppo, who goes by the name Hawkeye, and his two Indian companions, Chingachgook and Uncas, Chingachgook’s son, the only surviving members of the once great Mohican tribe. Hawkeye says that Magua, a Huron, has betrayed the group by leading them in the wrong direction. The Mohicans attempt to capture the traitorous Huron, but he escapes.
Hawkeye and the Mohicans lead the group to safety in a cave near a waterfall, but Huron allies of Magua attack early the next morning. Hawkeye and the Mohicans escape down the river, but Hurons capture Alice, Cora, Heyward, and Gamut. Magua celebrates the kidnapping. When Heyward tries to convert Magua to the English side, the Huron reveals that he seeks revenge on Munro for past humiliation and proposes to free Alice if Cora will marry him. Cora has romantic feelings for Uncas, however, and angrily refuses Magua. Suddenly Hawkeye and the Mohicans burst onto the scene, rescuing the captives and killing every Huron but Magua, who escapes. After a harrowing journey impeded by Indian attacks, the group reaches Fort William Henry, the English stronghold. They sneak through the French army besieging the fort, and, once inside, Cora and Alice reunite with their father.
A few days later, the English forces call for a truce. Munro learns that he will receive no reinforcements for the fort and will have to surrender. He reveals to Heyward that Cora’s mother was part “Negro,” which explains her dark complexion and raven hair. Munro accuses Heyward of racism because he prefers to marry blonde Alice over dark Cora, but Heyward denies the charge. During the withdrawal of the English troops from Fort William Henry, the Indian allies of the French indulge their bloodlust and prey upon the vulnerable retreating soldiers. In the chaos of slaughter, Magua manages to recapture Cora, Alice, and Gamut and to escape with them into the forest.
Three days later, Heyward, Hawkeye, Munro, and the Mohicans discover Magua’s trail and begin to pursue the villain. Gamut reappears and explains that Magua has separated his captives, confining Alice to a Huron camp and sending Cora to a Delaware camp. Using deception and a variety of disguises, the group manages to rescue Alice from the Hurons, at which point Heyward confesses his romantic interest in her. At the Delaware village, Magua convinces the tribe that Hawkeye and his companions are their racist enemies. Uncas reveals his exalted heritage to the Delaware sage Tamenund and then demands the release of all his friends but Cora, who he admits belongs to Magua. Magua departs with Cora. A chase and a battle ensue. Magua and his Hurons suffer painful defeat, but a rogue Huron kills Cora. Uncas begins to attack the Huron who killed Cora, but Magua stabs Uncas in the back. Magua tries to leap across a great divide, but he falls short and must cling to a shrub to avoid tumbling off and dying. Hawkeye shoots him, and Magua at last plummets to his death.
Cora and Uncas receive proper burials the next morning amid ritual chants performed by the Delawares. Chingachgook mourns the loss of his son, while Tamenund sorrowfully declares that he has lived to see the last warrior of the noble race of the Mohicans.