The Chinese drama "When We Were Young" is a nostalgic coming-of-age story set in 2018. It follows Yang Xi, a tomboyish high school student training for a long-distance run that could boost her college entrance exam scores. Her summer training is disrupted when she gets injured in a lab explosion caused by a new transfer student, Hua Biao.

Hua Biao is a hot-headed genius who ends up taking Yang Xi's place as class president. This unexpected turn of events sparks a rivalry between them. As the story unfolds, they navigate the challenges of high school life, including friendships, academics, and the blossoming of young love.

"When We Were Young" is a romance comedy with themes of friendship, competition, and the bittersweet memories of youth. It explores the struggles and triumphs of teenagers as they chase their dreams and discover who they want to be.