Tulbar and Hekla, indentured thieves to Sheik Fouaz, are tasked with raiding the Sarkian Mine works in the mountains of fire. He is sending them to enrich their masters coffers. Strange things are encountered, sulfurous hot springs with abnormally lush vegetation. And rumors of illness among the workers who mined the strange green mineral. Lesions and Neurological problems. Before the first night is through, Hekla has already succumbed to the effects of the mine.. but something more sinister is in store for Tulbar.
After the debacle at the caravan site, Conan has taken it upon himself to follow the dancing girl who the Guards were so keen to find earlier. His suspicions hold true, she is the missing princess they were seeking. She makes clear the situation that exists between her and Guardsman Zaius. He is to marry her, and become King. But she desires the power of monarch for herself.
The two debate the status of religion in the Hyborian world, a topic which Conan seems quite knowledgeable about. Before anything untoward can happen however they are beset upon by Temple Guardian Zaius and wild accusations. The girl prevents Conan from killing Zaius on the spot, and city law prevents Conan from getting satisfaction from Zaius by way of a Duel, for now their quarrel must be left to simmer, since it can't be brought to a boil.
Meanwhile, High Priest Khummanos, is journeying to the Mines with the strange mineral, taking with him several servants from his own tribe who live beside the shore of the sea of Shartoum. He has also in his employ Tulbar, whom he found upon arrival. The Priest and his slaves cast several statues from the strange mineral, with incantations. But industrial mishaps are not uncommon, and Tulbar, alas, does not survive. No matter, the priests goal is met.