Jill Marshall was born in Manchester, UK. Her first book, Jane Blonde Sensational Spylet, broke publisher Macmillan's record for a debut children's book. Since then, Jill has written another 27 books, from picture books to tween/teen fiction, through to young adult and adult standalone novels, and published by Macmillan, Penguin, Hodder and JMB. Most recently she has pulled five characters and their series - including Jane Blonde - into a planet-saving uber-team aka SWAGG. Jill is a Sunday Times Top Ten bestselling author whose books have been published worldwide in a dozen languages and two dozen countries. Educated at Cambridge and Winchester Universities (UK), Jill has Master's degrees in history and in creative writing for children. She divides her time between UK's Peak District and New Zealand.