Professor Davidson and his lovely daughter Diana search Africa for the Lost City of Zoloz. Legend pegs it to be the source of a vast hidden treasure. Their search is hindered by a local crook, Singapore Smith, who wants the treasure for himself. It is further complicated by Dr. Bremmer, an international criminal, who plans to destroy the peace with the local native tribes and build a secret air base at Zoloz. Fortunately, the Phantom, who is also Diana's fiancé, is more than a match for the two villains. Unfortunately, the ravages of time have damaged parts of the soundtrack negative on Chapter 11 beyond repair. This chapter has been digitally restored by Movie Stuff of Houston, TX, using a cast of actors to recreate some of the voices based on the original studio cutting continuity.