After a tumultuous childhood in India and schooling in England, Ashton Pelham-Martyn takes a post with the British Corps of Guides on India's northwest frontier. There he struggles to reconcile his Indian upbringing with his place in Anglo society, and he courts the beautiful Belinda Harlowe. After returning from Afghanistan, Ash is transferred to a desk job with an army regiment. He finds a good friend in Wally but clashes with the other officers. As punishment for a brawl, Ash must escort a caravan of princesses to be married--including Anjuli, his childhood playmate.
Prince Jhoti arrives to accompany the procession and brings with him Biju Ram, Ash's old enemy. When an attempt is made on Jhoti's life, Ash tries to discover the saboteur in their midst. Meanwhile, his feelings for Anjuli deepen, even though she is en route to wed another man. The procession arrives at Bhithor, where negotiations with the rana do not go well. Forced to camp in a militarily indefensible position, the convoy seems to be at the prince's mercy, but Ash has a few tricks up his sleeve. He also urges Anjuli not to marry the rana.
Ash returns to Mardan, where the Corps of Guides has been fighting across the border. British envoy Cavagnari signs a treaty with Afghanistan's emir and establishes an embassy in Kabul. Wally leads a force to secure the legation, while Ash accepts an assignment to spy among the natives. After making a last stand at the embassy, Ash journeys home. There, he learns that Anjuli's husband is near death; she and her sister, Shushila, will have to commit suttee, immolating themselves on his funeral pyre. Ash concocts a desperate plan to save his lover.
