Su Qingqing transmigrated into the palace and discovered the emperor had set up a deadly harem conspiracy to find someone from his late queen's hometown. She played dumb to survive and found clues to a time-space door left behind in the late queen's blood-written testament. After surviving an assassination at a palace banquet, she obtained the emperor's bloodstained handkerchief but was cornered. The eunuch Gao sacrificed his life with a blood ritual to send her back to the modern world.
