Sibéal Pounder is the author of Bad Mermaids Make Waves and the Witch Wars series. She has written for publications including the Guardian, fashion-trend forecaster WGSN, Vogue.com, and the Financial Times, where she was the resident philanthropy columnist for the How to Spend It section for four years-interviewing everyone from Vivienne Westwood to Veronica Etro. www.sibealpounder.com @sibealpounder Jason Cockcroft graduated from Falmouth School of Art and has been working as an illustrator of children's books ever since. He won the Blue Peter Book Award for his work on Geraldine McCaughrean's retelling of A Pilgrim's Progress and was the illustrator on the original covers of the final three Harry Potter novels, as well as Bad Mermaids Make Waves. jasoncockcroft.co.uk