In 1945, Harbin has come under the rule of Japan's puppet state known as Manchukuo. Communist agent Song Zhuo Wen successfully infiltrates Harbin Secret Service where Guan Xue holds a post as the chief of special police.
In the early 1930's Shanghai, various forces raged in the storm and the society was in turmoil. Ding Yiqing, the daughter of a wealthy businessman from Ningbo, came to Shanghai alone and met Communists underground workers Dong Hongyu, Lin Mosheng, Du Ying and many others. They experienced the outbreak of the War of Resistance against Japan in 1938. After the Pacific War in 1942, they completed various tasks for the revolution, letting the passion of youth burn as they strive for their ideal day.