A story within a story within a story, not so much nested as intertwined like one of those theoretical geometric shapes you find in advanced mathematics. Not merely a book but a piece of art where the medium mirrors the story within, as the house's interiors change shape so does the book, and occasionally you'll find yourself turning it sideways and upside down while reading. Nothing short of a work of genius. The horror is not so much scary as deeply unsettling, as you follow the explorers attempting to map a structure that defies understanding. I wouldn't recommend the book to just anyone, it's better suited for people who like puzzles, riddles, and getting lost.