All those missing pieces you wanted? The darkest ones? What's broken and still true? Here they are, Casey. They're yours to [...] don't ever say I didn't warn you.

Elliot Bancroft is many things-privileged, snarky, motherless-but she's also the girl who committed a horrific act as a child, so to most people she's a freak. That's why no one's surprised when her father moves the beautiful but mysterious Casey Anderson into their home and forbids him to ever leave her alone.

Stuck together inside her dark dungeon of a house, Casey becomes an unexpected source of light and happiness in Elliot's sheltered world. But their budding romance is soon complicated by Elliot's best friend, the perfect and dependable Michael Harris, who's been harboring feelings of his own for Elliot. And when Elliot makes a shocking discovery about Casey, she's doubly torn-between the boy who already knows her darkest secrets and the one who pulls her deepest truths to the surface.

Then everything changes the night a reckless decision lands Elliot in jail, where she begins writing letters to Casey-even though he visits her weekly. As her sentence draws to an end, so does Elliot's emotional unraveling of their history, and she faces the same gut-wrenching questions once again.

How far will she go to protect Casey's heart? And when he holds the darkest pieces of Elliot in his hand, will Casey still want to claim hers?