Elle Edwards, who has been told she's a product of her mother's sinful mistake, has never gone to school, never met a teenager her own age, never even been allowed off of her grandparents' property. Convinced that their granddaughter is infected with evil, Myra and Prescott Edwards believe that only the harshest child-rearing methods will prevent Elle from becoming an instrument of the devil.

Emmie Wilcox was only six when her sister, Roxy, was thrown out of their New York City apartment. Their stern father's military style left no room for rebellion, and Roxy was continually defiant and rebellious. Emmie is obedient, respectful. Two sisters, total opposites - yet Emmie is secretly obsessed with the mystery and imposed silence surrounding Roxy. She wants excitement, and being a good girl all the time is harder than it seems. Finally, Emmie goes behind her father's back to track down and spy on the sister she can't help but be fascinated with.

Caroline Bryer is the daughter of a very conservative TSA agent and former military brat, Morgan Bryer. Her mother, Linsey Bryer, is a descendent of the Sutherland real estate family. Their organized, suburban life in Colonie, New York is rigorously regulated and leaves little room for deviation from the norm. When Linsey, Morgan, and Caroline attend the wake of their neighbor Mr. Gleeson, they meet his charming daughter Natalie “Nattie” Gleeson, who works for the American ambassador to France. Linsey and Nattie strike up a fast friendship.

As identical twins, Haylee and Kaylee Fitzgerald have always done things in exactly the same way. Under their mother's guidance, their every outfit, every meal, and every thought was identical. But now things are different. With Kaylee back at home after her sister's betrayal, her life has been turned inside out. Both her mother and Haylee are away, and Kaylee's alone and more lost than ever.

Left on a train platform in an unfamiliar village, Saffron Faith Anders is certain her father will return shortly, like he promised. She holds out hope even as the hours pass and the station grows dark. When a strange old woman with a large umbrella approaches and inquires about her situation, Saffron doesn’t immediately trust the imposing do-gooder, but with the chances of her father returning growing ever slimmer, she agrees to rest at the old woman’s house. Her stay was supposed to be for a few minutes, but Saffron soon realizes she has been confined to a house of dark secrets.