Ling Zhao, the former intelligence chief who was demoted to work as a snow sweeper, wrote three lines of passwords on the snow with his frozen fingers, which actually made the enemy head of state burn incense and commit suicide. She is not a madman, but the last key to the empire. Xiao Lingyi, a female staff officer from the enemy country, deciphered her signal and discovered that this shadow in the snow was the only witness to her childhood blood debt. The silence of the border guard commander Zhou Jin, the whispers of the postman Yun Niang, and the dreams of his adopted son Helian Jin are all tearing apart the curtain of lies. When the truth emerges, who is the real traitor?
