Three greedy men, desperate foreigners in South America have a map, that promises them fabulous riches ( the usual lost Inca gold), but no money to finance an expedition. Starrett, their leader asks Nicholas Graydon who has the dough, for aid in Quito, Ecuador and a big share of the uncountable, presumed profits. A mining engineer, graduate of some obscure school called Harvard (never heard of it either). So Graydon ten years after leaving the university needs to make something of his life, even taking a chance with such unsavory looking gentlemen, he doesn't expect this document to be authentic (none are). Mr. Graydon is an educated man and the chasing of legends , is not what Nicholas worked for so hard, anyways there are valuable minerals in the stunning Andes Mountains, still you can imagine transportation during the early 20th Century, is very primitive indeed here. Eight burros are attained, six local Indians as guides to do all the difficult tasks required, Roads? They make them sometimes, the packers are nervous too many strange incidents have occurred, in this forbidden isolated, territory so the superstitious Indians leave without permission, in the small hours of the the night taking half of everything, why does this happen in every adventure story (plot enhancement)? Selfish people must be very sound sleepers, (like logs) the rest of the group hardly misses them and go on, without the anxious guides. After a long tiring hike, of many days the first interesting thing they find ... Suarra, an unbelievable beautiful girl in this the remotest part of the Andes, what race is she? Not Indian or Spanish or any known tribe on Earth. Graydon rescues the lady from Starrett's annoying advances, she had been draped with a great amount of precious jewels... Making him Starrett instantly an enemy of the others ( nobody likes a double- crosser), and prisoner too. Not to worry Suarra returns, leads them into the Hidden Land (Yu-Atlanchi) where people live forever, a place full of ferocious dinosaurs and the riders on them, also invisible flying Demons (messengers, as they like to be called). The Face in the Abyss in a dark, terrifying, colossal cave with a moving weird head and great voice inside a rock (the Evil One), just call him ... Nimir. Graydon gets a little scared who wouldn't ? Almost collapses, not to mention also there Lizard-men and spider-men too, real big spiders not the Hollywood kind. Incredible death defying rapid travels through caves and tunnels, an unknown somethings is after the terrified intruders. The strangest part of all Snake Mother, half reptile and half woman Adana, she's thousands of years old , however doesn't look it. The outsiders see a magnificent, ancient city by a gorgeous lake, arriving at a rather unhealthy moment though, for the four newcomers, civil conflict breaks into the open between the Snake Mother's, and the Dark Lord's rather less respectable, bloodthirsty followers . Fought with mostly deadly rays, of different, gorgeous colors ( the old-fashioned sharp swords and spears too) . Graydon and Suarra fall madly in love, while he fights for the snake. In any war there is always time for a little romance nevertheless, yet how old is Suarra. This is a land of unlimited life if they can avoid an unpleasant and unforeseen "accident". Nicholas is afraid to ask the lady her age, it's not nice to do so...Mr. Merritt shows again here why he was such an incomparable artist, he may have been a purple prose writer still no one else did it better....