James Pierce is one of the lesser-known film Tarzans, partly because this picture -- his debut as an actor -- has apparently been lost, and partly because it was his only starring role. He is a fairly significant Tarzan, however, because his association with author Edgar Rice Burroughs led to a romance with Burroughs' daughter, Joan. Pierce and Joan wed, and the union lasted 40 years. This Tarzan film was one of the better late-'20s productions from low-budget filmmaker J.P. McGowan. Here, Tarzan is the master of a golden lion and ruler of the jungle, including the natives who have an amazing diamond mine. Estaban (Fred Peters) learns of the "city of diamonds" and in his attempt to get his hands on the gems, he kidnaps Ruth (Edna Murphy) and a guide. Tarzan, his lion, and the natives come to the rescue. Ruth is restored to her sweetheart, Burton (Harold Goodwin), while Tarzan goes home to his wife, Jane (Dorothy Dunbar).