Katherine Rundell is the #1 New York Times bestselling author of the Impossible Creatures series. Her other books for children include Rooftoppers, Cartwheeling in Thunderstorms, The Wolf Wilder, The Explorer, and The Good Thieves. For adult readers, Rundell has written Vanishing Treasures: A Bestiary of Extraordinary Endangered Creatures and Super-Infinite: The Transformations of John Donne, which won the Baillie Gifford Prize for Non-Fiction. She was the recipient of the British Book Award for Book of the Year and Author of the Year. She grew up in Zimbabwe, Brussels, and London, and is currently a Fellow of St. Catherine's College, Oxford.

Ashley Mackenzie is a Canadian artist and illustrator with a special affinity for dragons, dryads, and all magical creatures.