From the award-winning author of The Bone Maker and The Lake House comes a haunting novel about sisterhood and grief, where difficult truths must contend with the corrosive power of unchecked lies.

After her mother dies, Hannah doesn't know how to exist without her. Literally. In fact, Hannah's not even certain that she does exist. No one seems to see or hear her, and she finds herself utterly alone. Grief-stricken and confused, her sense of self slowly slipping away, Hannah sets out to find new purpose in life-and answers about who (and what) she really is.

Hannah's only remaining family is her older sister, Leah. Yet even Leah doesn't seem to notice her. And while Hannah can see and hear her sister, she also sees beautiful and terrible things that don't-or shouldn't-exist. She learns there's much more to this world than meets the eye and struggles to make sense of it all.

When Hannah sees Leah taking the same dangerous path that consumed their own mother-where lies supplant reality-she's desperate to get through to her. But facing difficult truths is harder than it looks...