The Qing is rumored to dealing in the human trafficking of girls from Joseon. Yeo Ji is recruited as an undercover investigator on the case. Prince Yeoning is unhappy at Yeo Ji being constantly in danger. Meanwhile, Moon Soo, as a new member of Saheonbu, is trying to endure all the hard training. The palace officials show that they don't acknowledge the Crown Prince by not showing up at the Prince's first-morning lecture.