Kim, officially Kimball O’Hara, is the orphaned son of an Irish soldier and nursemaid who both died when in his infancy. He lives in the Indian city of Lahore under British rule in the late nineteenth century, spending his days begging and running errands for locals. Though Kim is white, he was raised—or at least, housed—by a half-caste Indian woman and speaks and thinks natively in Hindu. Because of this, Kim often passes as Indian, nicknamed “Friend of All the World” for his deep familiarity with the land and its people. The only evidence of Kim’s true identity is an amulet he wears around his neck, which contains legal documents from his father.
In Lahore, Kim befriends a kindly old Tibetan lama, named Teshoo Lama, who is on a journey to free himself from the “Wheel of Things” by discovering the “River of the Arrow.” Excited by the promise of adventure, Kim joins the lama as his chela (disciple). Leaving Lahore, Kim agrees to deliver an important message for Mahbub Ali, a horse dealer and longtime friend and employer of Kim’s who secretly works for the British government. Arriving in Umballa, Kim delivers the message, overhearing an important military conversation about an upcoming war.
Kim and the lama travel to the Great Trunk Road—India’s major thoroughfare. While the lama meditates, Kim revels in the variety of people and pleasures on the road. Among them is a fiery old widow with an impressive retinue of guards and servants. Taken by the lama’s status as a holy man, the widow invites Kim and the lama to travel with her. However, Kim is captured while spying on a regiment of soldiers who turn out to be the Mavericks, his father’s former regiment. When the regiment’s two religious leaders, Father Victor and Reverend Arthur Bennett, discover Kim’s true identity, they decide to take him in.
Kim tries to escape, but Mahbub turns him in, conspiring with Colonel Creighton—Mahbub’s employer and the recipient of Kim’s message—to send him to St. Xavier’s school in Lucknow. Kim is angry at Mahbub’s betrayal, but Mahbub promises him it is for the best. The lama, though sad at the loss of his chela, offers to pay for Kim’s expensive schooling. Kim travels to Lucknow with Colonel Creighton, who tells him of his intention to turn Kim into a chain-man—a British informant in the Great Game, a war of espionage between British and Russia.
For the next three years, Kim receives education at St. Xavier’s, assimilating into sahib—or white—culture and excelling at math and map-making. On occasion, the lama visits. During school breaks, Kim disguises himself to roam amongst “his people” in the countryside. Over time, however, Kim also begins to train as a chain-man during breaks, going abroad with Mahbub to conduct foreign espionage and learning secrets of the trade—like how to don disguises—under Lurgan Sahib. In all these areas, Kim shows great potential, and after three years Kim, now fifteen years old, is released from St. Xavier’s.
To reimmerse him in the native culture of India, Kim is allowed to travel with the lama for six months. Before leaving, Mahbub and Hurree Babu, another high-ranking British informant, employ the services of Huneefa to magically darken Kim’s skin. Afterward, Babu inducts Kim into his secret society, giving him an amulet and special set of keywords to identify himself as a “Son of the Charm.”
Kim travels to meet the lama in Benares, helping to cure a Jat farmer’s sick child along the way. The farmer joins Kim and the lama, now reunited, on their train ride to Umballa. On the train, Kim encounters a fellow Son of the Charm, codename E23, disguised as a Mahratta, and uses his new skills to help him evade detection by the police. E23 thanks him, but the Jat farmer, scared of Kim’s seemingly magical powers of transformation, flees. Alone, Kim and the lama travel to the old widow’s residence, where they are met by Hureee Babu disguised as a doctor.
Once alone, Hurree Babu congratulates Kim on helping E23 and asks for his assistance on a new mission involving two foreign agents in the Northern mountains. Kim agrees, and together they coerce the lama to take a detour into the mountains for his health. Kim and the lama begin their ascent up the mountains, with Kim promising to maintain a consistent distance from Hurree Babu on the trail. However, the lama is galvanized by the mountain air—he is from the Tibetan mountains originally—and often takes Kim on shortcuts that lead them off the main trail.
Hurree Babu encounters the two foreign agents, a Frenchman and a Russian. Pretending to be the servant of a local Rajah, Hurree quickly befriends the two men, feigning distaste for the British empire to gain their trust. They take Hurree on as a guide, eventually running into Kim and the lama on the main trail. However, a fight breaks out when the Russian strikes the lama, and the men’s servants, or “coolies,” run off with their bags. Hurree feigns solidarity with the foreign men’s, but he instructs Kim to join the coolies and retrieve key documents from their bags.
Kim and the lama follow the coolies to Shamlegh, a mountain village, and Kim retrieves the foreign men’s documents from their bags. Kim hears news from Hurree Babu, who requests to join them in Shamlegh. However, the lama demands that they leave, citing his concerning behavior, like his impulse to hurt the Russian, as evidence that his time in the mountains has led him spiritually astray.
Once down the mountains, the cart-drivers leave and Kim carries the lama on his back, an exhausting ordeal. Kim has an emotional breakdown, and the lama reassures him of his merit as a chela. Hearing of their struggles, the rich widow sends for them, and she cares for Kim upon their arrival. Kim recovers quickly and learns that Hurree Babu is at the widow’s estate. Relieved, Kim gives Hurree the agents’ documents. Hurree commends Kim for his actions and regales him with his own adventures with the two agents.
Hurree leaves and Kim goes to rest under a nearby tree, surrendering himself to “Mother Earth.” He is woken by the lama who tells him his Search has concluded, detailing how his soul left his physical body to join the Great Soul. However, instead of abandoning himself entirely to the Great Soul, the lama explains that he decided to remain behind to instruct Kim in his own path to salvation. The lama smiles at the thought of the salvation awaiting his beloved Kim.