When Zhang Yun, a modern Ming historian, was explaining the history of Emperor Chongzhen in the Forbidden City, he accidentally discovered a bronze mirror engraved with mysterious runes. He fainted and fell to the ground after touching it.
- After waking up, he found himself in Beijing, the 16th year of Chongzhen's reign, and was hunted down by Dongchang agents as a suspicious person.
- In a critical moment, he was rescued by Zhou Xin, a member of the Royal Guards. Zhou Xin became interested in this "madman" who behaved strangely but knew the government affairs well.
- Zhang Yun relied on his historical knowledge to accurately predict the movements of the court the next day, which shocked Zhou Xin and decided to take him to meet Chongzhen.
