When Shen Yu was born, Grand Tutor Jiang Shen locked her into the underground "Wu Guang Pavilion" on the grounds that "the Jade Evil Spirit was born" and poisoned her aunt who was protecting her daughter. When she was twelve years old, her stepmother, in order to protect her daughter, forced her to marry Prince Yongning, who would go crazy and hurt people on Shuo Day. She escaped with an iron nail.
After that, she became the "Mrs. Blackstone", specializing in punishing the powerful without harming the innocent. However, she was slandered by her stepmother as an "ogre" and was hunted down by the patrolling city guards. By the moat, she threw herself into the river and feigned death, but was rescued by the third prince Jiang Sheng.
Jiang Sheng gradually warmed to her, but when he went on an expedition, the emperor met Shen Yu by chance and named her "Yu Concubine". Jiang Sheng returns, and the two secretly have an affair. Shen Yu found out that his mother's death had the emperor's private seal, and Jiang Sheng also discovered that he was the baby that the queen snatched from the street.
They had the evidence of a cowardly emperor, but in the end they supported the young emperor, with Jiang Sheng as the auxiliary king and Shen Yu as the regent.
Purpose: revenge