In December 1941, Japan expands the occupation of its neighboring countries to Southeast Asia. The railway from Tianjin to Nanjing in East China became a key military transportation route, heavily guarded by Japanese soldiers. Railroad worker Ma Yuan leads a team of freedom fighters. Using his deep knowledge of the train network, he and his men sabotage it, ambushing Japanese soldiers and stealing supplies to feed the starving Chinese. Although the freedom fighters have no weapons of their own, they employ whatever tools are at hand, including shovels, loose railway track planks and diverted trains. The local Chinese call the unlikely heroes the “Railroad Tigers”.