And then a wealthy Upper East Side woman pays her a visit. Amber Randall is concerned about her twin sixteen-year-olds, Lark and Fox, who have acted and looked very different since they returned from spending the summer with their British father in the UK. She tells Jessica that her children have unnaturally perfect skin for teenagers and have lost all the tics and habits that made them who they were. They are not Lark and Fox, she tells Jessica. Something has happened to them.

To find out more, Jessica travels to Essex to talk to their father and once there meets Belle who is living a curiously isolated existence in a run-down farmhouse with her guardian Debra. Jessica knows that Lark and Fox had spent the summer with Belle—but can this unworldly teenager really be responsible for Lark and Fox’s new personas?

Jessica soon discovers that, behind Belle and Debra, evil geniuses are playing a dangerous game with technology in order to make the world a "better place", not caring who gets hurt, maimed or even killed in the process. Can Jessica stop them from wreaking destruction on a whole generation of young people? Nothing is certain in Lisa Jewell’s gripping and most imaginative novel yet.

LISA JEWELL

Lisa Jewell was born in London in 1968. Her first novel, Ralph’s Party, was published in 1999. It was the best-selling debut novel of the year. Since then she has published another sixteen novels, most lately a number of dark psychological thrillers, including The Girls and Then She Was Gone. Lisa is a top 10 New York Times and number one Sunday Times author who has been published worldwide in over twenty-five languages. She lives in north London with her husband, two daughters, two cats, two guinea pigs and the best dog in the world.