Professor Clark Ashton Scarsdale, a brilliant scholar-explorer, leads a small party of conveniently unquestioning recruits to the mysterious underground haunts of an ancient extraterrestrial civilization, somewhere east of Tibet. Sinister evidence of present occupancy mounts, in Copper's would-be-sonorous prose style, as the luckless five explore the vast subterranean labyrinth. Sci-fi horror of the school which mercifully subjugates sci to vague intimations of doom, and very nicely put together, even if the writing is careless.