Description: Readers' Choice Collection. The Ultimate Scientific Reasoning Challenge: Five Books! - Top Popular Mystery Book of the Year - A Must-Have for Every Elementary School Student. A Must-Buy for Parents! The series has won the Taipei Deep Cultivation Reading Award and the Elementary and Middle School Students' Book Selection Award. Mystery stories that kids won't be able to put down. -Mind-Bending + Scientific Reasoning + Detective Story- ----- Nine-year-old detective Ai Xiaopo, whose crime-solving abilities have been greatly upgraded, and Ji Feifei, an alien who has modified his spaceship and returned to Earth, travel through interstellar space and form the Pocket Detective Alliance once again--using scientific knowledge to solve mysteries in everyday life!
