The story's title character, whose name means "Olaf the Eye Shutter", is a figure from Scandinavian folklore. He is roughly equivalent to the Sandman in English-speaking countries. Ole Luk-Oie is said to make children feel sleepy and go to sleep. He is also said to reward good children by giving them pleasant dreams. The story describes the visits which Ole Luk-Oie makes to a boy called Hjalmar on seven consecutive nights and the dreams which Hjalmar has.