It makes you feel the altitude before it makes you feel the dread. That's the trick of a pilot filed under Adventure and Sports while quietly running on At the Mountains of Madness logic: every pitch of ice, every gasp of thin air, animated with the kind of weight-bearing detail most productions save for a finale. It started life as a Call of Cthulhu tabletop scenario, the sort where the sanity rolls become legend at the table, and the anime keeps that shape intact. The climb is the horror. The score does half the lifting, swelling like a summit push and then curdling right when the mountain stops being a mountain. This exists because fans paid for it to exist, and eleven-odd minutes in you understand exactly what they were funding.

A tourist flight bound for Antarctica disappears without explanation. Searchers sent to the spot where its signal was lost find no aircraft. Instead they discover a previously unknown mountain range that rises higher than Everest. The discovery draws some of the world's boldest climbers, who set out to scale the impossible peaks, but terrible horrors wait near the top. This pilot special for a crowdfunded project adapts a tabletop RPG scenario that mixes the Cthulhu Mythos with mountaineering. It is presented as an early step toward a full-length feature film.