Kai, a left-behind child living in a village, wants to meet his parents in the city during the summer holidays, but learns that his parents are hiding the fact that his mother is pregnant with a second child, so he has to stay in the mountains in this summer. After an anxious and scorching day, Kai sleepwalks towards the river to play with water. Kai’s grandparents use superstitious methods to treat Kai's sleepwalking, but he occasionally dreaming of scenes of fire.