While researching church history in Viborg, Denmark, the narrator's cousin stays in a Danish inn. While staying in Number 12, he notices that his room seems to grow smaller and his furniture sometimes vanishes. After hearing dancing next door, he assumes it comes from Number 13; however, upon discussing the matter with the inn-keep, he learns that there is no Number 13. He asks the inn-keep to visit his room at night. While talking, the protagonist and the inn-keep hear ominous singing in the room next door. They check Number 14, but learn that its occupant thought the singing was theirs. Then they find the 'nonexistent' door to Number 13. A clawed hand attacks them, and they attempt to bust down the door but break through the plaster wall. The occupants of 12 and 14 spend the night in a double bedded room. The narrator meets his cousin the next day and relates the tale to him.
