Tarzan: Battle for Pellucidar (Edgar Rice Burroughs Universe #2)

Tarzan of the Apes, Jason Gridley, and the crew of the airship O-220 return to Pellucidar, the world at the Earth’s core, on a wartime mission to stop the Nazis from obtaining a powerful superweapon. But when the Lord of the Jungle’s murderous adversaries partner with the Mahars—Pellucidar’s dethroned reptilian overlords—and his adventurous granddaughter Suzanne goes missing on a reconnaissance mission, can Tarzan prevent the conquest and enslavement of all humanity in both the inner and outer worlds?