Ilona discovers what it means to have a mother who is a modern woman and a father who is a 19th-century gentleman ghost.After being hit by a car and taken to the hospital, Ilona starts to realize she's different from other people, and that her mother has hidden the truth from her. She sneaks out of the hospital in order to discover the truth.A mysterious boy named Archer guides her through Brooklyn and introduces her to Hendrick, the man who claims to be her father—though he died in 1890. Ilona must discover not only what she must do to rid the city of Soll, a sadistic and powerful spirit, but also what it means to be half ghost. She proves what her mother told her—love is stronger than death.