Cressida Cowell is the author and the illustrator of the bestselling How to Train Your Dragon book series, and the author of the Emily Brown picture books, illustrated by Neal Layton.

How to Train Your Dragon has sold over 8 million books worldwide in 37 languages. It is also an award-winning DreamWorks film series, and a TV series shown on Netflix and CBBC. The first book in Cressida's new series, Wizards of Once, publishes in September 2017.

Cressida is an ambassador for the National Literacy Trust and the Reading Agency and a founder patron of the Children's Media Foundation. She has won numerous prizes for her books, including the Gold Award in the Nestle Children's Book Prize and 'Philosophy Now' magazine's 2015 'Award for Contributions in the Fight Against Stupidity'.

She grew up in London and on a small, uninhabited island off the west coast of Scotland and she now lives in Hammersmith with her husband, three children and a dog called Pigeon.

Mark Nicholas was born and brought up near York. He was artistic from an early age and studied modelmaking at the University of Bournemouth. He began working as a modelmaker after graduating, but always had a love of children's picture books, inspired by Mick Inkpen's Kipper and a short stint as a playground designer.

After a successful career which included working on the CBBC stop-motion animation 'Rubbadubbers', in 2012 he decided to seek a career in illustration and gained a place on the MA Children's Book Illustration Course at Cambridge School of Art.

Whilst studying on the course, Mark won the Hachette Children's Group's Carmelite Prize for Illustration to illustrate Tantrum O'Furrily, by Cressida Cowell, as well as the Macmillan Lara Jones Award. When not illustrating children's books, you'll find Mark wandering the fields of Wales with his wife and daughter, picking up inspirational textures for his illustrations.