Young Heidi spends her summer vacation with her grandfather in a cabin in the mountains. One day, while walking through the green Alps with her friend Peter, the girl finds an injured lynx. The children decide to rescue it and bring it back to the family. But their plans want to interfere with the villain - a greedy businessman Schneittinger. He plans to cut down the whole forest and catch all the animals. Heidi and Peter have to protect not only the little lynx, but also all the animals in the forest, which is their home.