Youth Party is a spin-off show based on Youth With You 3, and it is based on the stylish and cool lifestyle of young people. The program takes 12 real life scenarios of youth as its theme, and designs games associated with the scenarios as the mechanism for social, so that in the familiar scenarios and interesting games, the social of trainees can happen for real and youth can grow together.

Zhang Xiaomei, commander of the Beiyi division, seeks revenge against Crown Prince Li Ye for orchestrating his father's death. When Zhang captures Li Ye's top spy, Zhu Qingzhu, he sees a chance to expose the prince. However, Li Ye betrays Qingzhu, using her as a scapegoat to avoid punishment. Just as she faces execution, Zhang Xiaomei spares her life and brings her into his household. As they grow closer, they fall in love, only for Li Ye to reemerge, determined to reclaim Qingzhu and prevent her from finding happiness with another man.

Suffering from a mysterious illness, noble concubine Su Qin encounters a black-robed kidnapper "Bing-zhong-bing" in the palace. To marry Lu Huan, Prince Ningan and plot regicide, they face danger together, their bond growing amid turmoil.