Freaky thing, living with someone else’s vital organ. Sixteen-year-old Charlotte learns that lesson the hard way when she receives a life-saving heart transplant. Even though her doc says all is well, she knows the heart’s in trouble in a way science can’t measure. To make matters worse, her dead donor is trapped in an after-life that Charlotte wouldn’t wish on an enemy. It’s up to her to find out what the heart needs, pay her debt to her donor, and free them both from an awful fate. If she’s smart, she’ll also find out what a heart is really for.