In this eerie tale presented as a found manuscript, the diary of occult investigator Alonzo Typer reveals his descent into madness after entering the cursed Van der Heyl mansion in upstate New York. As he explores the abandoned house, Typer uncovers disturbing relics and forbidden lore linked to ancient, otherworldly forces. The entries grow increasingly unhinged as he loses his grip on reality—until the final pages hint at a horrifying fate beyond comprehension.