Claire’s older sister Sophie has always been the brave one – even last year when she was sick with an illness no one could name.
So when the girls find a ladder up the chimney of their new home, it’s Sophie who leads the way into Arden, a land of magic, castles, terrifying wraiths and whispered tales of real unicorns.
All Claire wants is to forget about their discovery, but when Sophie vanishes, she will have to summon all her courage to climb back up the ladder and find her sister …
and the secret of the unicorns.