Introduction to the episodes of the TV series "Tunnel War". Full introduction to the plot of Tunnel War from episode 1-40 and the grand finale. In the autumn of 1942, the Japanese North China Dispatched Army launched a brutal large-scale sweep against the anti-Japanese base areas in the Ji Zhong Plain. Colonel Yamada of the Japanese army stationed in Changshan County, leading the puppet army detachment headed by Tang Binghui, aggressively advanced towards Gaojiazhuang, a stronghold village for anti-Japanese resistance.