Kim befriends an aged Tibetan lama on a quest to free himself from the Wheel of Things by finding the legendary "River of the Arrow".

On the way, Kim learns about the Great Game and is recruited by Mahbub Ali to carry a message to the head of the British Secret Service in Umballa.

He is caught and mistaken for a thief, but the regimental chaplain identifies Kim by his Masonic certificate, which is sewn into an amulet that he wears around his neck.

Upon learning of Kim's connection to the regiment, the lama insists that the boy comply with the chaplain's plan to send him to an English school in Lucknow.

He is also trained in espionage (to be a surveyor) while on vacation from school by Lurgan Sahib, a sort of benevolent Fagin,[4] at his jewellery shop in Simla.

After three years of schooling, Kim begins to take part in the Great Game, joining the Secret Service at 20 rupees a month.

Kim obtains maps, papers and other important items from the Russian agents, who are working to undermine British control of the region.

It is a tale of adventure...It is the drama of a boy having entirely his boy's own way...and it is the mystical exegesis of this pattern of behaviour..." This reviewer concludes "Kim will endure because it is a beginning like all masterly ends..."[9][10] Nirad C. Chaudhuri considered it the best story (in English) about India – noting Kipling's appreciation of the ecological force of "the twin setting of the mountains and the plain...an unbreakable articulation between the Himalayas and the Indo-Gangetic plain".