I often write novels based on fairy tales, folktales, myths, and religious stories. They attract me for three reasons. They have stood the test of time, and I want to harness that power. Their plots grip me so hard I can barely breathe. They challenge me: how do I interest readers in a story they already know?

What draws me in is a narrative black hole — one I not only can’t escape but plunge into with abandon; if the light won’t come to me, I go to it. For example, Gretel burns up the witch in the oven. What?! How’d she get that chance? Why didn’t the witch simply turn her into chicken powder? Unless, of course, the witch was an accomplice in her own demise (see my novel The Magic Circle). Another example: in Homer’s Iliad, a soldier left on an island to die of a lethal serpent bite is found alive ten years later. How? He was neither doctor nor magician. Who saved him? (This was the impetus for my novel Sirena.) Many old tales can be summarized by a series of seemingly disconnected and improbable events. How could the maiden in “Rumpelstiltskin” live happily ever after with a monarch who had threatened to kill her (Spinners); how did Snow White survive in that glass coffin (Dark Shimmer)? I try to make coherence of improbabilities by looking for medical and/or psychological reasons that might account for them. It’s puzzle-solving, often of the emotional/mental kind — not a clean intellectual game, but a bloody one that leaves me sleepless. I want to give readers the consolation of understanding why things had to go as they went…especially if how they went is otherwise horrifying (Iphigenia being told her father must kill her, for instance, in The Great God Pan).

Some puzzles willingly lend themselves to solutions that feel sensible to me given the characters’ worldviews. That makes me believe it isn’t luck; instead, there is profound truth buried in these classics. For that reason, I use details from the oldest version available to me. Sometimes those details don’t jibe with modern versions, so it’s fun to surprise readers (Jack climbs down the beanstalk with a hen, not a goose, in Crazy Jack; Cinderella’s “fairy godmother” figure is a fish in Bound). Other times, those details are so familiar, they are boring; hence a greater challenge for me.

This brings me to what I’ve learned about writing from these retellings: people will read classic tales repeatedly if offered new points of access. One could do that by changing plot — which isn’t for me since I love the plots. Another way is to focus on new understanding of characters (as mentioned already). A third is to set the story in an unfamiliar place and saturate the reader with details that thrill: an ugly duckling, but in Tasmania, where wallabies box (Ugly); three little pigs, but in Kenya, where aardvarks jump (Mogo, the Third Warthog). A fourth way is to create a new character whose perspective allows revealing insights: a woman frog who teaches our prince-turned-frog how to survive (The Prince of the Pond); a stowaway who views Noah’s family as would an anthropologist even as she herself struggles to survive (Storm); a boy with cystic fibrosis who recognizes that the pied piper can’t solve everyone’s problems (Breath).

We accept a prince turned lion (Beast) or Rapunzel’s braids reaching the ground (Zel) because we know those tales; they’re a part of our Western storytelling tradition. But sometimes I give readers classics from other cultures with which they might not already be familiar. Their lack of experience with those tales can make ready acceptance of any fantastical elements harder to swallow. How can we comprehend a purse that gives unlimited money (The Wager, from Sicily), or a princess turned slave (Hush, from Iceland), or a ship of women pirates in medieval times (Hidden, from Denmark)? My method has been to zero in on details of history, so that readers can explore a new time and place, first making the unfamiliar seem more concrete and then letting the fantastical elements do their wondrous job. As a child, books let me travel, and I was greedy for that — now I try to give readers similar opportunities to experience a wider world.

From the May/June 2015 special issue of The Horn Book Magazine: Transformations.