The film tells the story of a "new mission" from the Monster Hall. Faced with a series of mysteries, Xiaohei and his senior sister Luye embark on a new adventure to find the truth.

"Mom, I'm sorry. Please don't die." When Henry realizes death is at his mother's doorstep, he strikes a deal with a lifespan dealer to give years of his own life to his ailing mother. Now, his mother is a 20-year-old college student with a full life ahead of her, and Henry devotes his remaining days to helping her live life to the fullest. But things turn complicated when his friend falls in love with her!