The drama tells the story of a Chinese female college student who, after swapping identities with her twin sister who is a Japanese spy, embarks on a series of events. The whole play begins with the sister attempting to infiltrate the Chinese side by replacing her sister, only to find that the sister has turned the tables on her, impersonating her in a thrilling "spy game within a game."

During the 1937 Japanese invasion, three half-brothers from the Luo family reunite and, led by the eldest, Gu Shimin, join the resistance. When one brother uncovers a Japanese plan for a deadly chemical weapon, the brothers unite to infiltrate the enemy and destroy the factory, playing a key role in the war effort.