Pellucidar

Set in the imaginative hollow world of Pellucidar, this fantasy series follows David Innes and Abner Perry as they navigate a primitive civilization filled with prehistoric creatures, including dinosaurs. The narrative centers on their quest to liberate humanity from the oppressive Mahar rulers. David's return to Pellucidar is driven by the desire to find his friend Abner and his love, Dian, as they confront conflicts that arise from their initial discovery and work towards establishing a new human civilization.