In 1945, the Kuomintang and Communist forces fought for the Shandong Plain County. Yu Chengshan, the platoon commander of the 45th Brigade of the National Army, and the soldiers Vulga and Cao Gen were captured by the 36th Regiment of the Eighth Route Army, and Liao Gaoxuan, the commander of the 45th Brigade, sent a special attack team to rescue Yu Chengshan in vain.　　Japan surrendered, and Cao Gen and Vulga were willing to truly become the Eighth Route Army, but Yu still wanted to return to the Kuomintang troops. When the 36th Regiment was marching to the northeast, Yu Chengshan and Balga slipped away and rescued Zhang Ying, director of the Women's Rescue Association. Liao Gaoxuan led the 45th Division to capture Yizhou, and Yu Chengshan rescued the seriously wounded regiment commander Wang Beifeng.　　The 36th Regiment was upgraded to a division, and Wang Beifeng ordered to go to Fucheng, where the 15th Division of the National Army was stationed, to make trouble and assist the troops to take Beishun City, and Fucheng was also captured by the People's Liberation Army. Wang Beifeng surrendered to Liao Gaoxuan, and Liao Gaoxuan's subordinate Chu Duyun rebelled.　　Wang Beifeng was ordered to attack Yizhou, Yu entered the city to rescue Liao Gaoxuan, Chu Duyun killed Liao Gaoxuan, Yu blew up the bunker, and Yizhou was conquered. A group of captive soldiers represented by Yu Chengshan became real revolutionary fighters in the battle to liberate the northeast.