Somewhere in the unexplored heart of Africa, a part of this Earth had been taken over by an intelligence from outer space. Such was the message that reached the explorer Hareton Ironcastle, member of the famous Baltimore Gun Club. In that hidden and transformed valley would now be found monsters and pre-humans not to be seen anywhere else. Such a challenge could not be ignored...

The account of Ironcastle's expedition of daring but inexperienced amateurs became one of the classic novels of the French writer, J.-H. Rosny aîné, who was a contemporary of Verne, Wells, and Edgar Rice Burroughs.

Philip José Farmer, Hugo winner and chronicler of the adventures of Tarzan and Doc Savage, translated and retold Rosny's 1922 novel, L'étonnant voyage de Hareton Ironcastle, making it a marvelous adventure novel to stand alongside the works of Burroughs, Haggard, and Farmer himself. Farmer's 1976 version, published in paperback only, followed Rosny judiciously, while adding certain surprising embellishments of his own.

This handsome new edition boasts the same stunning cover art and six interior illustrations as the original paperback-by the legendary Roy G. Krenkel!