Plot summary

In the present day 1970, 121-year-old Jack Crabb (Dustin Hoffman), the oldest living man in the world, who resides in a hospice, is recounting his long and colorful life story to a curious historian (William Hickey). Among other things, Crabb claims to have been a captive of the Cheyenne, a gunslinger, an associate of Wild Bill Hickok, a scout for General George Armstrong Custer, and the sole white survivor of Custer's force at the 1876 Battle of Little Bighorn. Having been adopted by the Cheyenne and reared in their culture, Crabb tells the Historian that he has perspective on both Caucasian and Native American life in the 19th century.Flashing back to 1859, the 10-year-old Jack and his older sister Caroline (Carole Androsky) survive the massacre of their pioneer parents' wagon train by the hostile Pawnee warriors. Found by a Cheyenne warrior, Jack and his sister are taken back to a Cheyenne village. Caroline manages to escape on horseback, but Jack is reared by good-hearted tribal leader Old Lodge Skins (Chief Dan George). Life among the Cheyenne proves to be idyllic, though Jack unwittingly makes an enemy of another boy, Younger Bear (Cal Bellini). However, Younger Bear eventually owes his life to Jack, who saves him from a Pawnee warrior. Jack is given the name "Little Big Man" because he's short but very brave.In 1865, when Jack is age 16, he is captured by U.S. cavalry troopers after skirmish between them and the local Cheyenne. Jack then renounces his Native American upbringing in order to save himself from being killed by the Army sergeant who captures him. After his interrogation and debriefing, and being that he is still a minor, Jack is put in the foster care of Reverend Silas Pendrake (Thayer David) and his sexually frustrated wife, Louise (Faye Dunaway), who tries to seduce Jack. Jack cannot accept the contradiction between Louise's piety and sexual appetite. When Jack finds Louise one day seducing the owner of a local soda shop/pharmacy, he leaves the Pendrake household and renounces both his foster parents and religion.A year or so later, Jack becomes the apprentice of the snake-oil salesman Merriweather (Martin Balsam). The two are tarred and feathered when their customers realize that Merriweather's products are fraudulent. One of the angry customers happens to be Jack's sister, Caroline. Once Caroline realizes that one of the men she helped to tar and feather was her brother, they happily reunite. She attempts to mold her brother into a gunslinger named the Soda Pop Kid (after his favorite beverage). Jack meets Wild Bill Hickok (Jeff Corey) at a saloon, and Hickok takes a liking to the young man. When Hickok is forced to kill a man in self-defense, Jack loses his taste for gun slinging and Caroline deserts him.Another year or two later, Jack becomes a partner in a general store and marries a Swedish woman named Olga (Kelly Jean Peters). Unfortunately, Jack's business partner turns out to be a thieving scoundrel and Jack is forced to close the store. The famous cavalry officer George Armstrong Custer (Richard Mulligan) happens upon the scene and suggests the couple re-start their lives by moving further west.Jack and Olga set out, but their stagecoach is ambushed by Cheyenne hostiles. Olga is abducted and Jack sets out in search for her. During his quest, he is reunited with Old Lodge Skins, who is overjoyed Jack has returned to the tribe. Younger Bear has become a contrary (a warrior who does everything in reverse) and, having been humiliated by Jack years before, is still bitter. After a short stay with the tribe, Jack continues his search for Olga.He eventually becomes a "muleskinner" in Custer's 7th Cavalry, hoping to obtain information on Olga's whereabouts. He takes part in a battle against the Cheyenne, but when the 7th troopers begin killing unarmed women and children, Jack becomes enraged and turns on them. Nearby, Jack discovers a Cheyenne woman, Sunshine (Aimée Eccles), giving birth. He saves Sunshine from the marauding troopers and returns with her to Old Lodge Skins's tribe. Sunshine becomes his wife and, the following year, bears him a child of their own. Jack again encounters Younger Bear, who has undergone another life change. No longer a contrary, Younger Bear is now the henpecked husband of the long-lost Olga, who has become a Cheyenne squaw. Olga does not recognize Jack, who makes no attempt to remind her of their previous relationship. Sunshine asks Jack to take in her three widowed sisters as wives and to father children with them. He is reluctant at first, but finally agrees and has sex with all three in succession.One day during the winter season, Custer and the 7th Cavalry make a surprise attack on a Cheyenne camp in Oklahoma (to be known as the Battle of Washita River, which took place on November 27, 1868). A now-blind and elderly Old Lodge Skins is saved by Jack, but Sunshine and their child are killed along with her sisters. Jack tries to infiltrate Custer's camp to exact revenge. At a crucial moment, with knife in hand, Jack loses his nerve, and is mocked by Custer for it.Flashing forward eight years later in 1876, a disheartened Jack has become the town drunk in Deadwood, South Dakota. While in a drunken stupor, he is recognized by Wild Bill Hickok, who gives him money to clean up. When Jack returns to the bar, Hickok is shot and killed. With his last breath, Hickok expresses a dying wish involving a widow he was having an affair with. Jack goes to see the widow, a prostitute who turns out to be Louise Pendrake. Jack gives her the money that Hickok intended for her to use to start a new life.Jack soon becomes a trapper and hermit. His mind becomes unhinged after coming across an empty trap with a severed animal limb. Poised at the edge of a cliff, he prepares to commit suicide. Jack suddenly hears the faint chords of the traditional cavalry tune Garryowen echoing through a valley and spots Custer and his troops marching nearby. Jack decides to exact revenge. Custer, who remembers that Jack once tried to assassinate him, hires him him as a scout, believing anything he says will be a lie, thus serving as a reverse barometer.Jack leads the troops into a trap at the Little Bighorn on June 25, 1876. Before the attack, Jack truthfully tells Custer of the overwhelming force of Native Americans hidden within the valley of the Little Bighorn. The arrogant and overconfident Custer does not believe him and leads the 7th Cavalry to its doom. During the frantic battle, Custer begins to rave insanely while Jack is wounded. Ignoring the closing circle of massed Sioux and Cheyenne warriors, Custer points his pistol at Jack. Before he can pull the trigger, the deranged Custer is shot in the back with several arrows and killed by Younger Bear, who removes the unconscious, wounded Jack from the battle by carrying him to Old Lodge Skins' tepee pretending that he is carrying a fellow warrior. Having thus discharged his life debt, Younger Bear tells Jack that the next time they meet, he can kill Jack without becoming an evil person.Some days later at the Indian camp, the recovering Jack accompanies Old Lodge Skins to a nearby hill, the Indian Burial Ground, where the old man, dressed in full Chief's regalia, has declared "It is a good day to die", and decides to end his life with dignity. He offers his spirit to the Great Spirit, and lies down at his spot at the Indian Burial Ground to wait for death. Instead, it begins to rain. Old Lodge Skins is revealed to still be alive, and says, "Sometimes the magic works, and sometimes it doesn't". They return to his tepee to have dinner.Back in the present, Jack's narrative abruptly ends and he dismisses the Historian who leaves the room. The film concludes with an extended shot of the elderly Jack sitting in his wheelchair and sadly staring into space.... thinking about the memories of a world which is no more.