As they journey to the Atai Mountains they are joined by Prince Michael, he attempts to reconcile with Tina but she refuses, and he heads back to Mallico. Tina finds comfort with Sir Michael Andrews, who has come to assist them. They reach the highest summit of Belukha and uncover a lost glacial city. After a dramatic battle with a mysterious tribe of wolf-men they follow the clues to South East Asia. In Bangkok they meet with Lady Jackson-Ward and Francis Glamour before heading into Cambodia. In the ruins of Angkor Wat they find more clues before an attack by winged creatures. They manage a daring escape as the ancient temple collapses. The girls head to Africa, not realising they are being pursued. The Tibesti mountain in the Sahara proves to provide them with the final clues as to the location of the lost fountain of fire, but not before a battle with the nomadic Tuareg warrior men in which Gaynor is kidnapped. After a dramatic rescue by Debbie and Tina they head towards South America. In the rain forests bordering Peru, Bolivia and Brazil, they discover the lost city of Paititi. The climax sees the girls attacked by Inca warriors, fighting against the mythical Gorillogators and finally coming face to face with Cassiopeia Von Collins in the temple of the lost fountain of fire. The evil Queen of Paititi unleashes Eontaguchu, the demon of time. While Tina and Debbie engage the monster Gaynor stuggles with Cassiopeia. Locked in combat the pair fall into the fountain of fire. Gaynor escapes as the centuries begin to reverse for Cassiopeia. She screams for Eontaguchu and the demon snatches her from the deadly fountain. In a blinding explosion of white flame they disappear and the temple begins to collapse. Our heroes make it out just in time as the city falls to ruins. They have discovered the truth but Cassiopeia Von Collins has escaped, somewhere across time and space...