Detective Shen Ting of the modern crime team chased the murderer on a rainy night and fell to her death. Her soul passed through the body of Shen Tingruo, a concubine who had been tortured in Daqi Prime Minister's Mansion. The eldest sister Shen Qingrou coveted her mutton-fat jade pendant and pushed her into a cold pond. When she was about to die, she was secretly rescued by Xiao Jueyuan, the regent who had been entrusted by the late emperor. Xiao Jueyuan was a young man fighting in northern Xinjiang, holding half of the power of the dynasty. He was investigating a major case of smuggling saltpetre and sulfur to collaborate with the enemy. The Shen family happened to be involved, and Shen Tingruo fell into his sight.
Shen Tingruo, who had died once, was no longer cowardly. She relied on her criminal investigation thinking and relied on injuries and physical evidence to reconstruct the truth about the drowning. She gave evidence in front of the Fushou Hall. She also met with her father with the account books that had been recorded for many years in exchange for evidence to make up for the evildoers. While carefully preserving the evidence that her aunt was chronically poisoned, she followed the clues of her old servant Sun San to trace the secret of saltpetre and sulfur, and accidentally discovered that the mutton-fat jade pendant given by the Queen Mother contained an incomplete secret seal.
She and Xiao Jueyuan met at Songfeng Pavilion. From mutual suspicion and testing, the two reached a limited cooperation. At the Queen Mother's birthday banquet, Shen Qingrou deliberately set up a trap and forced Shen Tingruo to perform in public. With ten years of modern classical dance skills, she stunned the audience with a stunning dance.
After the birthday banquet, the clues gradually gathered together. Shen Tingruo tracked down the ghost in the prime minister's house, and the secrets of the jade pendant's past slowly surfaced. The crises in the court and the back house broke out at the same time, Shen Chongshan's crimes were revealed, and various forces fought against each other. If Shen Tingruo protects the person she wants to protect, she and Xiao Jueyuan also break away from the fate of the chess pieces. True love grows out of the game, and they work together to quell the undercurrent of chaos.
