In 1906, Alipang and his Muslim Moro guerrillas are terrorizing the people of the Philippine island of Mindanao. A small group of army officers and native troops, led by Dr. Bill Canavan (Gary Cooper), are tasked with training the local police force to combat the fanatical followers. As tensions rise, Canavan's by-the-book approach clashes with Lieut. Terence McCool (David Niven), who tries to take a more aggressive stance against Alipang. The situation becomes increasingly dire as Canavan falls in love with Linda Hartley (Andrea Leeds), whose presence is met with suspicion and danger.