El mundo subterráneo es justamente famoso como el más sobresaliente de los libros de c-f escritos entre las primeras novelas imaginativas de H.G. Wells y las historias del futuro de Olaf Stapledon. Puede leérselo, si se quiere, como una emocionante novela de aventuras, pues en él se combinan, de un modo maravillosamente rico, un fondo de imaginación ilimitada con los hechos más sorprendentes.

Sydney Fowler Wright’s The World Below, published in 1929, is a time travel tale clearly patterned on H.G. Wells’s The Time Machine template: a time traveler relating his fantastical adventures to a skeptical cadre of friends and associates. And as in Wells’s story, far in the future human life on earth has evolved into a pair of separate and competing species. Wright’s strength lies in his beautifully detailed descriptions of the future world’s landscapes, creating a uniquely immersive experience for the reader. The action sequences are exciting and have a real swashbuckling flair, but these moments are few and very far between, as the primary downfall of the book is the frequent treatises on philosophical subjects (government, libertarianism, capitalism, socialism, justice, logic/reason, etc.) that, while intrinsically intriguing, routinely bring the story itself to a screeching halt. The World Below consists of two-thirds of an intended trilogy, with the concluding section never written. ( )