An unconventional professor invites four of his students to explore the mansion of the “Mad Hatter,” a figure from urban legend who was driven mad by mercury poisoning and sorrow. The professor assures them there’s no danger now: the peculiar, lumbering “caretakers” that roam the estate are simply servants who have suffered from inbreeding, and the Hatter has been deceased for many years. However, as the students begin to vanish one after another, the survivors start to doubt whether the professor’s experiment is genuinely scientific… and whether the Hatter’s madness didn’t just consume him, but also became contagious…