The Queen of Air and Darkness is so thematically complicated that it must provide much explanation for the reader to follow the action. To begin the tale with a dry disquisition about Anderson's ideas would probably lose readers. Instead, Anderson begins in the middle of the mystery. The opening scenes are of a fairyland of winged sprites and changeling children; without explanation, Anderson portrays an enchanted world that may hold the attention of an audience. Explanations come later and are mostly presented by Sherrinford.
The kidnapping of a child fits elegantly into the fairyland theme and provides motivation for Cullen and Sherrinford to uncover the reality of the magical Outworld. Anderson often uses mysteries to give his fiction narrative drive; in The Queen of Air and Darkness, the logical uncovering of clues makes for a logical development of his themes. The more the Outworld is explained, the more Anderson's ideas are explored.
The Queen of Air and Darkness belongs to an ill-defined literary subgenre called "science fantasy." It more often appears in novels, such as Andre Norton's Witch World (1963) and James H. Schmitz's The Witches of Karres (1966), probably because most magazines, with the exceptions of The Magazine of Fantasy and Science Fiction and Amazing Science Fiction Stories, want stories that are either science fiction or fantasy, not both at once.