Confessions of an Ugly Stepsister is a retelling of Perrault's classic "Cinderella". It's a fantasy only in a sense: the story itself has no magic, yet suggestions of magic permeate the text. This Cinderella story has the same characters as the original, but the perspective is reversed. Maguire tells his story from the viewpoint of one of the stepsisters, Iris, who is neither ugly nor evil, but multi-faceted and ordinary. Maguire's Cinderella is part fairy tale, part historical romance, and part lesson in morality. It's not solely about Iris, but about her mother, a woman named Margarethe Fisher who leaves England after the death of her husband and arrives in Holland with her daughters, Iris and Ruth, homeless and hungry.

The women find shelter with a painter and work with a tulip merchant, and the story progresses into a politically-correct tale of love and life. Maguire reworks the fairy tale into a realistic myth that empowers women and that blurs the divisions between beauty and ugliness, good and evil.