Half-caste British captain Alan King takes supplies to the outpost of Peshawar, India. On the way, his unit is ambushed by Karram Khan, a traitor and King’s former childhood friend. The commander at Peshawar, General Maitland, has brought his daughter Susan along with him. Although the British officers distrust Captain King because he is a half-caste, General Maitland treats him on the basis of his impeccable military record, even if he’s not so sure of his daughter's romance with the man.