GWENDOLINE

Captured by a trio of thieves at a Chinese port, Gwendoline, a courageous but naïve girl, is sold to a local casino-brothel owner, but after being rescued by Willard, a mercenary adventurer, she is reunited with her maid, Beth, after the latter's abduction by the same thieves who had earlier kidnapped Gwendoline.

Hired to transport an illegal cargo, Willard reluctantly agrees to take both women with him after Beth, withholding information vital to his livelihood, promises to divulge it only if he becomes their guide. Gwendoline, who has come to China to capture the butterfly that eluded her father, who had staked his professional reputation as a scientist on obtaining the insect, offers Willard $2,000 to take her and Beth with him to the land of the Yik-Yak, in which the butterfly may be found.

After escaping from the cannibal tribe of Kiops, the trio find the butterfly, but as she is about to capture it, Beth is captured and Gwendoline and Willard must enter an all-female tribe's underground lair to rescue the maid. The tribe is the vestige of the city of Pikaho, a primary diamond mining centre, which was swallowed by a volcanic eruption in the 12th century. Afterwards, the entire male population perished due to a disease spread by the eruption, and Pikaho turned into an all-women society considered nothing more than a legend. To ensure the survival of Pikaho, its Queen allows a victor among them to mate with any man who visits or is captured by the tribe. Aided by Beth and the Queen's henchman, D'Arcy, Gwendoline, disguised as a Pikaho warrior, wins this right.

While Gwendoline and Willard make love before the Queen, D'Arcy activates the volcano and he, the Queen, and the citizens of Pikaho are killed as Gwendoline, Beth and Willard escape. In the process, Willard is able to capture the elusive butterfly.

Gwendoline, Willard, and Beth escape the collapsing city of Pikaho after D'Arcy activates the volcano, resulting in the deaths of the Queen and the citizens. Willard successfully captures the elusive butterfly.

The climax ties the wild adventure together with a literal eruption, destroying the hidden matriarchal society and freeing the protagonists. The capture of the butterfly symbolizes the completion of both Gwendoline's personal quest and her father’s legacy. Survival and desire are intertwined, with the protagonists’ escape marking both liberation and the end of an era for the lost city.