Deep below the earth's surface, a mystifying subterranean seascape lurks, an archipelago bathed in inky blackness where suspense and horror hold court. Here lie strange islands and even stranger monsters, far beyond the realms of human imagination. In this domain, mankind is far from dominant; instead, madness and death rule supreme.
Pleading for mercy from the unknown creatures of the deep only leads to a slow, tortured existence. The trapped survivors gradually distort, losing what made them human, both physically and mentally, to the gloom as they remain trapped in this eternal obscurity. Their only hope? A perilous expedition into uncharted sea territories.
Fueled by determination, Charles embark on this daunting voyage aboard his steamship, aiming to reclaim humanity's past glory. Together with his crew, they sought a way out of this hidden sea world, a path back to the sunlit world above, where humans once stood tall.
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I read a few comments from Chinese readers that compared this novel with Lord of Mysteries because of similar elements: Lovecraftian, western fantasy, first industrial revolution, and steampunk. However, I have yet to finish reading Lord of Mysteries to do any actual comparison, but I do think those who have enjoyed that novel would enjoy this as well. Also, the author of LotM, Cuttlefish That Loves Diving, also did a shout-out for this novel, so I guess he approves of it too?

A price is always exacted for what fate bestowsaadapted from Zweigas Mary Queen of Scots.
aIam a nobody, with no time to notice the brightness of the sun.
aMy parents couldnat help me, and I wasnat highly educated. I had no choice but to make it on my own in the city.
aIad applied to many jobs, but no one ever hired me. Maybe itas because Iam not good at expressing myself, and Iam not the best communicator. I guess I just havenat shown enough ability.
aOnce, Iad eaten two loaves of bread over a three-day period. Hunger kept me up at night. At least I paid a monthas rent in advance, so I didnat have to face the cold winter wind outside.
aFinally, I found a job at the hospitalas morgue, keeping vigil over the dead.