Kate Morton's writing is superb.
The Authoress and a little girl board a ship in England. She tells the little girl to wait for her, but she never comes back and the little girl is left all alone, sitting atop her suitcase, on a wharf in Australia. Without a name and no one looking for her the portmaster is left with little choice but to take the four-year-old child in. She is given a name and a good life until her father, the portmaster, tells her she is not who she thinks she is. The now 21-year old Nell leaves everything and everyone she has ever known and eventually sets off to find the one person she thinks will give her the answers she so desperately wants - the Authoress.
The book switches between a time when Nell is searching for answers about who she is; to her granddaughter searching in England for the answers that Nell never had the pleasure of knowing; and further back to when the Authoress herself was growing up.
The book is unputdownable.