Sally Nicholls was born in Stockton-on-Tees, just after midnight, in a thunderstorm. She spent most of her childhood trying to make real life as much like a book as possible.

Her first book, Ways to Live Forever, won the Waterstones Children's Book Prize in 2008 and in 2015 her book An Island of Our Own was shortlisted for the Costa children's prize. Sally lives in a little house in Oxford, writing stories and trying to believe her luck.

Júlia Sardà has illustrated everything from classic children's books to concept art for merchandise and video games, and covers for the likes of The Clockwork Sparrow, Rose Campion and the Stolen Secret and Beetle Boy by M. G. Leonard.

She is the illustrator of the acclaimed The Liszts, Sweep and The Problim Children, and she illustrated One Day in Wonderland: A Celebration of Lewis Carroll's Alice by Kathleen Krull. Her illustrations of classic stories include Oliver Twist, Alice's Adventures in Wonderland and The Wizard of Oz.