1849. At sixteen, Harriet Cooper has only one person keeping her from ruin, her older sister, Mary. Their father, Sir Charles, is obsessed with his youngest child and because their mother is dead it is Mary who keeps watch over Harriet's bedroom door. But when Mary dies in London's cholera epidemic, Harriet becomes a prisoner in her own home, her father would rather she acted as his wife than his daughter and she can see nothing but horror before her. It seems impossible, but her only escape route is to flee after her cousin Edward who has recently emigrated to the new colony of New Zealand. Sheltered as her life has been, Harriet discovers untapped reserves of bravery and courage and manages to get herself on a boat bound for Wellington. But as soon as her father realises what she has done, he chases her across oceans and uncharted waters to the other side of the world, where thousands have gone seeking a new life and where Harriet thought he would never find her.