The Danube salmon is a species that inhabits mountain rivers and streams. Part of its life can be seen in this documentary, which presents the magical underwater world of the Drina and Vrelo rivers in an exciting and captivating way. A fish once on the brink of extinction now plays a key role in the species' recovery. The audience gets a rare glimpse of this critically endangered species, its biology, and all the factors that influence its struggle for survival. This story serves as a reminder that no living being on this planet stands above nature — not even humans.