Mr. Anderson, researching church history in Viborg, stays at the Golden Lion inn. He notices the absence of a room numbered 13 on the hotel register, yet repeatedly sees and even approaches a door marked "13." Disturbances grow-shadows, voices, a ghastly singing, and a clawed arm reaching from the doorway. At dawn, the room vanishes, leaving only a copper box with a cryptic document, hinting at dark sorcery tied to Bishop Friis's infamous tenant, Nicolas Francken.