Should you get into the car of someone you barely know? Hard to resist when the driver is Jessup Smith, the handsomest teacher in school. That night, he drives sixteen-year-old Phoenix and her little sister Sasha—both brilliant misfits—home. A few days later, their mother, Erika, lets herself be seduced by Mr. Smith. Not long after, he's moving in, filling the empty space left by Phoenix and Sasha's father, who left the family without warning last summer.

At first, Mr. Smith seems too good to be true. He can be a little strict and controlling, sure, but nothing to worry about. Until it begins: first a kick, then a slap. Soon Phoenix is descending into a violent nightmare, afraid of making the least mistake and desperate to protect her little sister. As Phoenix and Sasha feel their world closing in, help may come from an unexpected place.