In 1944, in eastern part of China, U.S.Army Major Baldwin and his volunteer team of demolition engineers are left behind the retreating Chinese forces. Their task is to slow down the Japanese advance into eastern China by blowing up bridges, roads, airfields and munitions dumps. They start by blowing up an American airfield and ammo dump. They receive the order to destroy a vital bridge over a mountain pass.The team uses a few army trucks to move around. At the bridge, they encounter a Nationalist Chinese Army unit in charge of guarding the bridge. Thanks to an American soldier who speaks some Chinese, Major Baldwin requests the permission, from the Chinese commander, to blow up the bridge.The Chinese colonel agrees but asks the American Major to do him a favor by also destroying a munitions dump located at some distance away.He also requests that Madame Sue-Mei Hung, the widow of a Chinese colonel, be transported by the American demolition team to the nearest major town.