Catherine’s first novel, Mirror Dreams, was completed when she was 14 years old. The book was published in 2002 and garnered comparisons with Terry Pratchett and Philip Pullman. She went on to publish a further seven young adult novels under her own name, earning her extensive critical acclaim and two Carnegie nominations for her novels Timekeepers and The Extraordinary and Unusual Adventures of Horatio Lyle.
While studying International History at the London School of Economics, she wrote an urban fantasy series for adults, writing as Kate Griffin. On graduating LSE she went to the Royal Academy for Dramatic Arts to study Technical Theatre and Stage Management.