This is a story about opposites, extremes, and the gray zones that are in between: autonomy and dependence; solitude and family; hope and despair; freedom and captivity; life and death. The tone is decidedly dark, but even in the darkest places it is possible to find happiness, love and belonging. Published as a YA novel, its protagonists and themes will appeal directly to teens, but also appeal to adults. Schwab joins the ranks of writers like Roald Dahl and Neil Gaiman, who have written fiction that is targeted at children, but will appeal, and speak to, older readers as well.