Gu Qingning, a top student in the history department, and Ye Zhaoxue, a former forensic doctor, travel across Dayong in a car accident. One is the legitimate daughter of an unjust servant, and the other falls into an alcoholic family. Two Suzaku pendants activate the "Twin Soul Contract", allowing the two to share vision and investigate the case side by side.
In order to clear up the grievance of Gu's father for "collaborating with the enemy", they uncovered the second prince's conspiracy to collude with Beidi and plot to seize Yongxi's defense plan. On the way, he meets King Jing Xiao Jue (who protects the first suspect), Dali Temple Shaoqing Lu Jingran (helps investigate the drug case), and is joined by Su Qingyu, a disciple of Yuntai Mountain, and Su Muyao, Taifu's niece.
Everyone avoids the pursuit of Xiyu Si, looks for defense plans, and solves the mystery of the series. In the whirlpool of the prince's struggle for the throne, they use the power of the soul contract and the justice of the family and country to write a legend of the two sisters clearing their grievances and protecting the Yong Dynasty.
Purpose: Break the clichés of "female competition" and "love attachment". Bestie love is the strongest card to break the situation.