Three-and-a-half-year-old Princess Jinyang, Sizi, accidentally travels between ancient and modern times. Not only does she bring back a miraculous medicine that can cure Empress Zhangsun, but she also takes modern-day lollipops, luosifen rice noodles, and tractors back to the Great Tang. Qiu Feng, a modern online novelist, unexpectedly becomes a "Divine Immortal Big Brother." He initially just wants to live peacefully while feeding the little girl, but unexpectedly attracts Princess Changle as well. In the end, he even becomes a royal son-in-law of the Great Tang and its Imperial Preceptor.