Cardiovascular surgeon Yun Yi purchases a "haunted" villa at a low price, only to discover that the so-called "ghost" is actually Princess Jinyang, Xiao Sizi, from the Great Tang dynasty. Xiao Sizi can traverse spacetime walls, stealing his modern delicacies like cakes and lychees. The man and child thus form a bond; Yun Yi's villa becomes Xiao Sizi's "food base", and modern foods like cola, yogurt, and fried chicken are brought back by her to the Great Tang, amazing royal members such as Li Shimin and Empress Zhangsun. As their interaction deepens, Yun Yi not only teaches Xiao Sizi how to read a watch and use a mobile phone, but also, upon her plea, travels through time to the Great Tang to treat Empress Zhangsun's asthma, starting a wondrous bond across time and space.