M.G. Leonard has made up stories since she was a little girl but back then people called them fibs or tall tales, so she didn't think to write them down. After a successful career in the music industry and the arts, she finally dared to put pen to paper. Her inventive stories about beetles, birds and trains are hugely popular. Her books have been translated into over forty languages and won many awards. In this, her most ambitious series yet, M. G. Leonard combines her passion for music, love of history, and instinct for adventure, to bring readers the Time Keys books.

Manuel sumberac is a Croatian-based illustrator and animator. He graduated from the Academy of Fine Arts in Zagreb where he was drawn towards the fascinating world of illustration. His work has been published and recognized in numerous book illustrations and covers, including The Dalemark Quartet, Orphans of the Tide, The Night Before Christmas and Steampunk Frankenstein, among many others. Manuel creates his illustrations using digital techniques combined with traditional media.