Tom Fletcher is a number-one bestseller and one of the UK's most popular children's authors.

The Christmasaurus was the biggest debut middle-grade novel of 2016 and was shortlisted for a British Book Award. Since then, Tom has published several more chart-topping children's novels including The Christmasaurus and the Winter Witch, The Christmasaurus and the Naughty List, The Creakers and the instant number-one bestseller The Danger Gang.

Tom also writes the incredibly successful Who's in Your Book? picture-book series and is one half of the author duo behind the Dinosaur that Pooped picture-book series too, which has sold over 1.5 million copies.

For older readers, Tom co-authors the Eve of Man series with his wife Giovanna Fletcher.

Tom's books have been translated into 40 languages, and to date he has sold over 5 million copies of his books in the UK alone.

The Christmasaurus is currently being developed by The Greatest Showman director Michael Gracey into an animated, feature-length movie with original songs written by Tom.

As well as his career as an author, by the age of 21, Tom had penned 10 UK number 1 singles and is the founding member of the band McFLY. The Brit Award-winning band has sold over 10 million records worldwide and Tom has also written songs for other artists including One Direction, Busted and 5SOS.

Greg Abbott is an illustrator and designer who lives in West Sussex, England. In addition to children's books, he has created art prints, apparel, toys, greetings cards, and other merchandise. Visit him on Tumblr at gregabbott.tumblr.com.