As a fantasy novel written by famous children's literature writer Xue Tao, the work Xiaoke within the Walls narrates with the first person. The leading character is taken to the Grey Town by a messenger with small handcart. The children lived in the town are all very cold and each does things in his own way. Afterwards, a giant frog monster invades the town. At this time, all the children begin to regain consciousness, take off their gray clothes and defeat the monster hand in hand. Again, they come back to the real world. The entire novel has a rational layout and the anteroposterior plots take concerted action with bold and believable imaginations, which is an excellent work for children's reading.