Paul Drummond and Billy Sparks make their third trip to Shumbus, the strange land within the Earth. When they arrive, Argo takes them on a journey to a land of people forgotten in time, who hold a key to the history of Shumbus... if only they can escape from them and get back home.

Paul Drummond and Billy Sparks make their third trip to Shumbus, the strange land within the Earth. When they arrive, Argo takes them on a journey to a land of people forgotten in time, who hold a key to the history of Shumbus... if only they can escape from them and get back home.