The City Beneath the Moon is a dark fantasy and cosmic mystery novel that follows scientist Dylan as he uncovers the hidden city of Aethelgard, a ghostly metropolis that materializes only under the full moon. As he explores its eerie streets, ancient machinery, and failing supernatural seals, Dylan discovers that the city is not merely abandoned-it is a colossal prison designed to contain an unimaginable force. Racing against time, he must unravel forgotten secrets before the ancient lock collapses and unleashes a nightmare upon the world.