Matt Oldfield grew up in Southampton, playing football with his brother Tom.

The two brothers are the authors of the bestselling Ultimate Football Heroes series – fun football biographies that tell the exciting life stories of superstars like Gareth Bale, Lionel Messi and Mo Salah, from the playground through to the pitch.

The Johnny Ball books are Matt's first fiction series. He lives in North London.

Tim Wesson was born somewhere in England. As a young boy he enjoyed climbing trees and drawing pictures of dogs in cars.

Eventually he became an illustrator who creates children's books. Tim doodles and paints whenever he can and likes to draw the first thing that pops into his head. He lives by the sea in Suffolk with his family.