The novel begins in the Indian city of Lahore. The time is the late nineteenth century and the British are in political control of India. Kim, a boy of twelve, is a street urchin. He is an Irish orphan, now living with a poor Indian woman.

Kim's father, a British soldier, left his regiment to work for the railroad. His mother died of cholera, and a few years later his father died from alcoholism and opium addiction. Around his neck Kim wears an amulet containing his father's papers and his own birth certificate.

Before his death, his father told him that these papers would one day make his fortune by identifying Kim to his father's old regiment. The emblem of this regiment, a red bull on a green field, signifies protection for the son of the former soldier. Thus, a strange kind of prophecy hangs over Kim's future...