Gu Yi Zhong, the young master of the famous Gu Family in Suzhou, graduated from the architecture department of a famous foreign university. During the War of Resistance Against Japanese Aggression, Gu Yi Zhong insisted on staying in Suzhou, under the name of protecting cultural relics, while in fact he actually actively participated in Anti-Japanese activities. In a rescue operation, Gu Yi Zhong was framed by the Japanese as a traitor within the party and betrayed overnight. Unable to prove his innocence and in order to find out the real traitor, Gu Yi Zhong took the initiative to infiltrate the Japanese army and became a hidden member of the Suzhou Secret Service Station. His hidden task is full of dangers.