Little tadpole Doudou has never seen his mother since birth. Seeing that others have mothers, he is very envious. Doudou went to ask the village chief and he said that Doudou’s mother was in the upper course of the river and was trapped by a large net. Doudou decided to look for his mother but was warned by the village chief that it is dangerous to go there. To reach the upper course of the river, one must pass through the dangerous rocky river bed and rapids. But Doudou is determined to find his mother. Doudou good friends Xiaoxiao and Beibei are willing to go together to help. So, the three good friends are on the road together! Welcome to the fantasy journey in the underwater world and embark on an exciting journey with Doudou to find his mother!