A group of Lisu people without a registered ID (Hukou) live their primitive life in the mountains by the Nujiang River in Yunnan. In addition to misfortune and hardships, they also have simple happiness.
This documentary is about a school in the mountainous area of Hunan and focuses on left-behind children in three families. Due to contradiction between backward rural appearance and urban development, the fate of the three generations interwoven together.