Synopsis：After an accident, Xia Cha and his grandson, Xia Zefang, exchange souls. Xia Cha's childhood friend died unexpectedly, his wife passed away early, and later, his son and daughter-in-law died in a car accident. Now, the only one left is his grandson, who has also passed away, leaving Xia Cha to live in his grandson's body. To prevent his grandson's life from coming to a halt, Xia Cha has no choice but to continue going to school in his grandson’s place. Now, a 69-year-old man’s soul is trapped in a 20-year-old boy's body. To return the body to his grandson, Xia Cha teams up with Ye Haiyuan, who is his neighbor, classmate, and roommate all in one. During their journey, they slowly discover the fated connection between them.