A spell-binding follow-up to the renowned novel that began the Lost World literary genre, King Solomon's Mines. The genre may seem identical, but the story-line builds up at its own fast pace. The exciting and thrilling tale set in a previously unknown Africa, in some ways, is more intense than King Solomon's Mines.

At the beginning, Quatermain has lost his only son and longs to get back into the wilderness. Having persuaded Sir Henry Curtis, Captain John Good, and the Zulu chief Umslopogaas to accompany him, they set out from the coast of east Africa into the territory of the Maasai. While staying with a Scottish missionary, Mr. Mackenzie, they are attacked by a Maasai group, whom they overcome heroically. They travel by canoe along an underground river to a lake (which turns out to be the sacred lake of Zu-Vendis) in the kingdom of Zu-Vendis beyond a range of mountains. The Zu-Vendi are a warlike white race isolated from other African races; their capital is called Milosis. At the time of the British party's arrival, they are ruled jointly by two sisters, Nyleptha and Sorais. The priests of the Zu-Vendi religion are hostile to the explorers as it is apparent they offended against the religion, but the queens protect them.