Antiquitas Lost tells the story of a boy named Elliott, a lonesome kid with deformities on his hands and feet who is uprooted from his home after his mother falls gravely ill. When they move to New Orleans so his grandfather can help care for her, Elliott learns that the old man's eighteenth century mansion hides an ancient secret. While checking out some eerie paintings and strange relics in the basement, Elliott strays through an ancient passage into a tumultuous parallel world, full of bizarre creatures and warring races. He has stumbled into Pangrelor, the most ancient of all worlds and "mother to all the stars in the sky." As he learns to navigate his new surroundings, he discovers wondrous abilities he never dreamed he possessed, and an abiding connection to the primitive, alien world that will forever change him. But he must proceed carefully. For he soon learns that his actions in the ancient world will impact the upcoming battle for Harwelden, Pangrelor's greatest civilization, and will also resonate all the way back to New Orleans, perhaps deciding whether his own mother lives or dies.