Catherine Isaac was born in Liverpool, England. She studied History at the University of Liverpool, then Journalism at Glasgow Caledonian University, before beginning her career as trainee reporter at the Liverpool Echo.
She rose to the position of Editor of the Liverpool Daily Post and wrote her first book, Bridesmaids, while on maternity leave, under the pseudonym Jane Costello. Her nine subsequent novels were all Sunday Times best-sellers in the UK.
'You Me Everything' is her first book writing as Catherine Isaac.
She lives in Liverpool with her husband Mark and three sons. In her spare time she likes to run, walk up mountains in the Lake District and win at pub quizzes, though the latter rarely happens.