Keith was born and brought up in Grimsby and knew from an early age that he wanted to be a writer. When he received 0% for his accountancy exams he decided to pursue his dream.

Since then, he has gone on to win the Angus Book Award and the silver medal in the Smarties Prize. He has twice been shortlisted for the Guardian Fiction Prize and was shortlisted for the Booktrust Teen Prize and the Scottish Arts Council Book Award. Rave reviews about his writing have appeared in every broadsheet. Keith was a judge for the Blue Peter Book Award, the Guardian Fiction Prize and the Bookstrust Teen Prize and reviews regularly for the Guardian.

Keith is now a full-time writer living in Edinburgh.