Four-year-old cute toddler Su Xiaoxiao lives in a 'normal' five-member family: dad is a security guard, mom is a housewife, older brother is a college student, and grandpa is a retired old man. In reality, the whole family are the strongest immortals of the three realms, disguising as mortals to protect Xiaoxiao by sealing their cultivation. Only Xiaoxiao has no spiritual root, the whole family desperately acts, Xiaoxiao naively breaks the act, resulting in endless laughs. When the final truth is revealed, Xiaoxiao uses the purest love to make the whole family understand that reunion is being together.