From a young age, Lovecraft was fascinated by the Antarctic. Likewise, he was very fond of Edgar Allan Poe's only novel, The Narrative of Arthur Gordon Pym of Nantucket, some of whose action takes place in the southernmost continent and which Lovecraft had called "disturbing and enigmatical." Consequently, it's not at all surprising that he would eventually write his own Antarctic tale, though its scope and content likely had other inspirations, including Lovecraft's own earlier story, The Nameless City, which appeared in 1921 and sometimes considered to be the first work of the Cthulhu Mythos. At 40,000 words, it is Lovecraft's second longest work of fiction (The Case of Charles Dexter Ward being the longest) and is generally regarded as among his most successful works as well, deftly combining the cosmic themes of his previous works with an explicitly non-supernatural approach to presenting them.
Like so many HPL stories, At the Mountains of Madness is told in the first person from the perspective of a survivor of a doomed expedition, in this case William Dyer, a geology professor from Miskatonic University. The expedition was to the Antarctic with the purpose "of securing deep-level specimens of rock and soil from various parts of the antarctic continent." Thanks to "the remarkable drill devised by Professor Frank H. Pabodie of our engineering department," the expedition uncovers some peculiar fossils that stirs the biologist of the expedition, Lake, to lead a party to the northwest of the main group in search of additional samples. While doing so, he discovers huge mountains over 35,000 feet in height ("Everest out of the running," he reports via radio), more fossils, and, later, the frozen remains of bizarre creatures:
"Objects are eight feet long all over. Six-foot, five-ridged barrel torso three and five-tenths feet central diameter, one foot end diameters. Dark gray, flexible, and infinitely tough. Seven-foot membranous wings of same color, found folded, spread out of furrows between ridges. Wing framework tubular or glandular, of lighter gray, with orifices at wing tips. Spread wings have serrated edge. Around equator, one at central apex of each of the five vertical, stave-like ridges are five systems of light gray flexible arms or tentacles found tightly folded to torso but expansible to maximum length of over three feet. Like arms of primitive crinoid. Single stalks three inches diameter branch after six inches into five substalks, each of which branches after eight inches into small, tapering tentacles or tendrils, giving each stalk a total of twenty-five tentacles.
"At top of torso blunt, bulbous neck of lighter gray, with gill-like suggestions, holds yellowish five-pointed starfish-shaped apparent head covered with three-inch wiry cilia of various prismatic colors. "Head thick and puffy, about two feet point to point, with three-inch flexible yellowish tubes projecting from each point. Slit in exact center of top probably breathing aperture. At end of each tube is spherical expansion where yellowish membrane rolls back on handling to reveal glassy, red-irised globe, evidently an eye.
"Five slightly longer reddish tubes start from inner angles of starfish-shaped head and end in saclike swellings of same color which, upon pressure, open to bell-shaped orifices two inches maximum diameter and lined with sharp, white tooth like projections - probably mouths. All these tubes, cilia, and points of starfish head, found folded tightly down; tubes and points clinging to bulbous neck and torso. Flexibility surprising despite vast toughness.
"At bottom of torso, rough but dissimilarly functioning counterparts of head arrangements exist. Bulbous light-gray pseudo-neck, without gill suggestions, holds greenish five-pointed starfish arrangement.
"Tough, muscular arms four feet long and tapering from seven inches diameter at base to about two and five-tenths at point. To each point is attached small end of a greenish five-veined membranous triangle eight inches long and six wide at farther end. This is the paddle, fin, or pseudofoot which has made prints in rocks from a thousand million to fifty or sixty million years old.
"From inner angles of starfish arrangement project two-foot reddish tubes tapering from three inches diameter at base to one at tip. Orifices at tips. All these parts infinitely tough and leathery, but extremely flexible. Four-foot arms with paddles undoubtedly used for locomotion of some sort, marine or otherwise. When moved, display suggestions of exaggerated muscularity. As found, all these projections tightly folded over pseudoneck and end of torso, corresponding to projections at other end.
"Cannot yet assign positively to animal or vegetable kingdom, but odds now favor animal. Probably represents incredibly advanced evolution of radiata without loss of certain primitive features. Echinoderm resemblances unmistakable despite local contradictory evidences.
"Wing structure puzzles in view of probable marine habitat, but may have use in water navigation. Symmetry is curiously vegetablelike, suggesting vegetable 's essential up-and-down structure rather than animal’s fore-and-aft structure. Fabulously early date of evolution, preceding even simplest Archaean protozoa hitherto known, baffles all conjecture as to origin.Not long thereafter, inclement weather ends radio contact between Lake's party and the main expedition led by Dyer. After a day without further word, Dyer becomes worried and decides to go, along with several others, to find out what has become of his colleagues. What this second party discovers is that Lake and all those with him, save one, were not merely dead but killed.
The crowning abnormality, of course, was the condition of the bodies - men and dogs alike. They had all been in some terrible kind of conflict, and were torn and mangled in fiendish and altogether inexplicable ways. Death, so far as we could judge, had in each case come from strangulation or laceration. The dogs had evidently started the trouble, for the state of their ill-built corral bore witness to its forcible breakage from within. It had been set some distance from the camp because of the hatred of the animals for those hellish Archaean organisms, but the precaution seemed to have been taken in vain. When left alone in that monstrous wind, behind flimsy walls of insufficient height, they must have stampeded - whether from the wind itself, or from some subtle, increasing odor emitted by the nightmare specimens, one could not say.Though unsettled by what he has seen, Dyer is nevertheless keen to unearth what happened to Lake and his companions, which spurs him to further exploration. This, in turn, leads to a series of discoveries that shake Dyer to his core and that form the bulk of the novella itself.
But whatever had happened, it was hideous and revolting enough. Perhaps I had better put squeamishness aside and tell the worst at last - though with a categorical statement of opinion, based on the first-hand observations and most rigid deductions of both Danforth and myself, that the then missing Gedney was in no way responsible for the loathsome horrors we found. I have said that the bodies were frightfully mangled. Now I must add that some were incised and subtracted from in the most curious, cold-blooded, and inhuman fashion. It was the same with dogs and men. All the healthier, fatter bodies, quadrupedal or bipedal, had had their most solid masses of tissue cut out and removed, as by a careful butcher; and around them was a strange sprinkling of salt - taken from the ravaged provision chests on the planes - which conjured up the most horrible associations. The thing had occurred in one of the crude aeroplane shelters from which the plane had been dragged out, and subsequent winds had effaced all tracks which could have supplied any plausible theory. Scattered bits of clothing, roughly slashed from the human incision subjects, hinted no clues. It is useless to bring up the half impression of certain faint snow prints in one shielded corner of the ruined inclosure - because that impression did not concern human prints at all, but was clearly mixed up with all the talk of fossil prints which poor Lake had been giving throughout the preceding weeks. One had to be careful of one’s imagination in the lee of those overshadowing mountains of madness.
At the Mountains of Madness is, in my opinion, a triumph, though not a flawless one. While Lovecraft clearly did a great deal of research to provide verisimilitude, there are occasions where the mask slips and I found my credulity stretched to its limits. Ironically, I think it's precisely because HPL did such a fine job in most respects that his infelicities seem all the greater. Even so, the novella succeeds in presenting a vast canvas onto which he paints a masterpiece of cosmicism. It's hard to gauge Lovecraft's success nowadays because the story he tells has influenced and been imitated by so many other stories in the decades since that its impact is artificially lessened. But make no mistake: without At the Mountains of Madness, we'd likely not have the "ancient astronauts" mythology that's become a regular feature of so much of pop culture. Thus, it's not only a worthy read in its own right but a seminal one as well.