The entire Su family was executed overnight, and the accusation of "collaboration with the enemy and treason" crushed generations of loyal people. The surviving Su Ningwei concealed her identity and sneaked into Prince Jing's Mansion to find out the truth, but unexpectedly confronted the person who oversaw the execution, Prince Jing Xiao Jue. Xiao Jue proposed to marry her on the grounds of "owing a debt", and a marriage full of hatred and mystery began, and the conspiracy deep in the palace gradually surfaced.