Emma Lysy

Catherine Helstone's brother, Laon, has disappeared in Arcadia, legendary land of the magical fae. Desperate for news of him, she makes the perilous journey, but once there, she finds herself alone and isolated in the sinister house of Gethsemane. At last there comes news: her beloved brother is riding to be reunited with her soon - but the Queen of the Fae and her insane court are hard on his heels. - from Goodreads.com