Every year, Huazi fish swim upstream to find ideal breeding grounds in the Inner Mongolia Autonomous Region in northern China. The ordeal speaks to the tough character of this plain-looking fish. But when many headless fish were found on the river bank at dawn, the question was raised: Who is the culprit? 

Watch more:

The life and death of Huazi fish | Episode 2: Hope of going against stream

The life and death of Huazi fish | Episode 1: Creature in the sea of death

(Cover image via screenshot)

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