After ten years of marriage, the male lead Jiang Songhan wanted to write a song for his wife to celebrate their anniversary. However, his wife had an affair with her "white moonlight" (the one she’d long cherished in her heart), leaving Jiang Songhan heartbroken. He resolved to take their daughter Xiaoqi and leave.Father and daughter were determined to prove themselves by participating in a children’s music competition, but they were repeatedly suppressed by the wife, who tried to force them to withdraw. In the end, Xiaoqi and her father launched a desperate counterattack.