Frey and Rafi are inseparable.... two edges of the same knife. But Frey's very existence is a secret. Frey is Rafi’s twin sister - and her body double. Their powerful father has many enemies, and the world has grown dangerous as the old order falls apart. So while Rafi was raised to be the perfect daughter, Frey has been taught to kill. Her only purpose is to protect her sister, to sacrifice herself for Rafi if she must.

In the Society, Officials decide. Who you love. Where you work. When you die. Cassia has always trusted the Society’s choices. And when her best friend appears on the Matching screen, she is certain he’s the one - until she sees another face flash for an instant before the screen fades to black. Now she is faced with impossible choices: Between Xander and Ky, between the only life she’s ever known and a path no has dared to follow...between perfection and the truth.

In Sloane’s world, true feelings are forbidden, teen suicide is an epidemic, and the only solution is The Program. Sloane knows better than to cry in front of anyone. With suicide now an international epidemic, one outburst could land her in The Program, the only proven course of treatment. Sloane’s parents have already lost one child; Sloane knows they’ll do anything to keep her alive. She also knows that everyone who’s been through The Program returns as a blank slate. Because their depression is gone - but so are their memories.

After the first wave, only darkness remains. After the second, only the lucky escape. And after the third, only the unlucky survive. After the fourth wave, only one rule applies: Trust no one. Now, it's the dawn of the fifth wave, and on a lonely stretch of highway, Cassie runs from Them. The beings who only look human, who roam the countryside killing anyone they see. Who have scattered Earth's last survivors. To stay alone is to stay alive, Cassie believes, until she meets Evan Walker. Beguiling and mysterious, Evan Walker may be Cassie's only hope for rescuing her brother - or even saving herself.

When fifteen-year-old Clary Fray heads out to the Pandemonium Club in New York City, she hardly expects to witness a murder - much less a murder committed by three teenagers covered with strange tattoos and brandishing bizarre weapons. Then the body disappears into thin air. It's hard to call the police when the murderers are invisible to everyone else and when there is nothing - not even a smear of blood - to show that a boy has died. Or was he a boy?