Tarzan is back in the newest novel of the groundbreaking Edgar Rice Burroughs Universe series!

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 routed 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?

Also includes the bonus novelette "Victory Harben: Clash on Caspak" by Mike Wolfer, as the Swords of Eternity Super-Arc hurls a young scientist to the prehistoric world of The Land That Time Forgot.