A stranger, lost while hunting in the moors of Brittany, fits the mysterious Demoiselle D’Ys. She invites him back again to her castle, and the two grow nearer. After a while, nevertheless, the stranger starts to believe that the various other inhabitants from the castle aren’t from the world as he understands it. “Demoiselle D’Ys” is a quintessential romantic horror story from Robert Chambers’ collection, The Ruler in Yellow.