Garth Nix was born in 1963 in Melbourne, Australia. A full-time writer since 2001, he previously worked as a literary agent, marketing consultant, book editor, book publicist, book sales representative, bookseller, and as a part-time soldier in the Australian Army Reserve.

Garth's books include the award-winning young adult fantasy novels Sabriel, Lirael, Abhorsen and Clariel; the dystopian novel Shade's Children; the space opera A Confusion of Princes; and a Regency romance with magic, Newt's Emerald. His fantasy novels for children include The Ragwitch; the six books of the Seventh Tower sequence; the Keys to the Kingdom series; and the Troubletwisters series and Spirit Animals: Blood Ties (co-written with Sean Williams).

More than five million copies of his books have been sold around the world, his books have appeared on the bestseller lists of the New York Times, Publishers Weekly, the Times and The Australian, and his work has been translated into forty-one languages. He lives in a Sydney beach suburb with his wife and two children.

Ursula was born and grew up in Sydney in a family of writers, and wanted to be a writer from the age of six. She is now the author of over 50 books for children and young adults and her work is published all over the world.

She has won several national literary awards, including the Victorian, Queensland and South Australian State Awards for literature, and has also won the NSW Premier's Literary Award a record five times, more than any other writer in the history of the awards.

Internationally she has been nominated for both the Hans Christian Andersen award and the Astrid Lindgren prize. She has a PhD in English literature and currently lives in Sydney.