Moko is an explorer. As he travels the world continent by continent, he makes many friends and discovers many natural phenomena which sometimes delight him, and other times scare him. Each animated episode recounts an adventure and takes an "original story" approach to explaining these natural phenomena. In this episode, one morning, Totemie takes Moko to pick wild mushrooms used for medicine by her people. There is a particularly rare one she is hoping to find. Moko suddenly slips in a crevice. Totemie runs to her village to get an old man who tells her that she should join Moko. When she does, Moko and Totemie discover an enormous cave filled with lakes in a rainbow of colors. They follow a stream that eventually becomes a river and on the river's bank they find the old man who is waiting for them. Before they leave to go back to the village, the old man asks them to keep this magical cave a secret and to keep the memory of it safe in their mind.