Ivy belonged to the shunned Carson family, who lived in the hills above town in a derelict Victorian mansion surrounded by neglected fruit orchards that had been handed down to her mother.

Ivy is dark, thin, beautiful, graceful and mature; Martha is blond, overweight, bucktoothed, clumsy, and cries easily.

They play regularly in a beautiful, magical part of the woods and develop an elaborate paracosm called the Land of the Green Sky.

As they grow older and enter their teen years, Ivy longs to be a ballet dancer and directs Martha into a career in drama.

Ivy's family responds to this crisis in the manner typical of when one of their own has trouble with the law - they pack up their old, red truck and, with no warning, flee in the dead of night.

Scholar R. Craig Roney presents The Changeling as representative of a move in 1970s fiction for older children's books to involve “a realistic character living in the real world who fantasizes (dreams or daydreams) to cope with some real or imagined problem.”[1] In discussing the traditional notion of “fairy as Other” in fairy tales, critic Ann F. Howey observes that the idea is “so integral to the changeling tradition that Zilpha Keatley Snyder, in a realistic children's novel, used it to dramatize one character's alienation.”[2] Snyder has said that both the fantasy game played by the girls in The Changeling and its evolution into the Green-sky series originated in childhood games she herself played in Ojai, California with relatives.