Posing as Tarzan's English cousin, Oliver Greystoke, the traitorous Englishman, Edwards, and his unscrupulous Russian agent accomplice, Rokov, enlist the help of Tarzan to secure uncut diamonds for England's military industry. Reluctantly, the lord of the jungle, along with the orphaned American boy, Joey, decides to lend a hand and guides the team through a scorching desert, unforgiving, cannibal-ridden territory and the land of the noble Waziri warriors. However, the road to the coveted gems is long and perilous, and there's more to Tarzan's new companions than meets the eye. Can mighty Tarzan give the impostors a taste of his savage fury and save helpless Jane from certain death?
—Nick Riganas