A plantation owner's marriage is tested by a bandit attack.

In Malaya, British rubber planter Jim Frazer and his American wife Liz learn that their neighbors, the Carters, have been killed by native bandits. Jim has grown cold and distant out of fear for his family's and the plantation's safety, and a distraught Liz, who is about to accompany their son Mike to England, secretly plans not to return to Malaya. Upon checking the plantation with his foreman, Nair, Jim discovers that the local laborers are being pressured to supply the bandits with food. Meanwhile, British inspector Hugh Dobson visits Liz, and guessing she intends to leave Jim, urges her to reveal her true feelings to her husband. On the road back to his house, Jim picks up Wan Li, a Chinese man who claims he was held up by the bandits and now needs a ride into town. Although he is suspicious, Jim agrees, stopping by the house first. There, Liz tells him that she feels he is sending her away, but Jim remains silent, and in a last attempt to feel close to him, she asks to accompany him to town. Along the way, Wan Li mentions Ah Siong, the bandit leader, and Jim's suspicions deepen. Once they reach town, however, Wan Li reveals that he is the uncle of the little servant girl who was wounded during the raid of the Carter's house, and Jim apologizes for distrusting him. While Liz goes to the hospital to visit the gravely wounded girl, Wan Li informs the police about his attack. As soon as he leaves the police, however, he is spotted by bandits and murdered. Liz and Jim spend a pleasant day together and then visit the British club, where Liz tells Hugh in private that she plans to ask Jim to join her in London, ignoring Hugh's pleas that Jim is needed in Malaya. On their way home, Liz and Jim's fears grow when they first see the Wan Li's body in the road, and then find their guard lying on the ground. Although they assume the worst, they soon discover the guard is only playing with Mike and his friend Mat. In the house, Jim falls asleep and, dreaming about his internment in a Japanese prison camp, calls out for Liz. When she asks him to return to England with her, however, he tells her he cannot, and she cries. Meanwhile, Mike is almost bitten by a cobra, but Mat frees his mongoose, which kills the snake. Over the next few days, Ah Siong's men increase their activities, killing workers and destroying rubber trees while warning the locals not to intervene. After one bandit is spotted in the jungle, he runs into town and corners Liz, who shoots him with a pistol, and then faints. Jim carries her home, where she awakens and discovers that their phone lines have been cut. Jim begins barricading the house and stocking the tunnel that runs under their property, and Nair moves in with his girl friend, Arminah. They set up two rings of lights around the house as defense, but just before dark, they learn that the power lines are out, and set a signal fire for help. Moments after dark falls, however, Nair fixes the electricity, and the lights blaze on to reveal the bandits swarming under the barbed-wire fence. Jim and Nair open fire, forcing the bandits to retreat, and Jim embraces Liz, admitting that he is sending her away only to protect her and their love. Hours later, Jim hears that the bandits are slashing all his trees, and impulsively races into the jungle, with Mat as a guide. When the bandits then resume their attack, Liz does not want Nair to shoot, fearing they may hit Jim, but after the rebels shoot out all the lights, Nair is forced to fight back. Just after Nair is wounded, Ah Siong calls out to Liz and lies that he is holding Jim. A bandit outside the fence trains his gun on Liz, but Jim sneaks up on him and throws a grenade, killing Ah Siong. The gunner turns away from Liz and pursues Jim through the jungle, but Jim is saved by the appearance of the police, who drop smoke bombs into the trees and scare off some of the bandits. Nair tries to crawl through the tunnel to rescue Jim and Mat, but collapses, and by the time Jim reaches the outside mouth of the tunnel, a bandit has entered before him. Hugh reaches the house with the police and covers the other end of the tunnel, allowing Jim to crawl in and trap the bandit. The bandit drops a grenade, forcing Jim to run toward the house, barely escaping before the tunnel explodes. Days later, Liz and Jim see Mike onto the train to London, having decided to remain behind together.