Eleni Markova has never felt emotion before: no happiness, no sadness, no anger, and no fear. She is one of the Hollow People, a group that came about a hundred years ago when a virus swept over the world, decimating the population and leaving only a fraction of people uncontaminated. Most of the contaminated died, and the few that recovered from the plague were changed forever. Their genes were altered, and they lost their ability to feel emotion. Now, a hundred years after the Hollow Virus, the only remaining human civilization thrives under the leadership of the Hollow People, and Eleni, a member of the City Guard, is a prime example of what a Hollow Person should be. But when terrorists attack the city, Eleni begins to experience what she never believed she could: fear. The foreign emotion runs rampant though her, causing her to flee for her life and abandon her post. With the city in chaos, Eleni must either trust her newfound emotions and a con artist named Oliver or let her home be destroyed.
What if death didn't apply to you? What if you could have infinite second chances at life? That's what the Numbers seem to have, endless chances at life. They are mutants who come back to life every time they die. But, with the Numbers System in place, their chances of survival are zero. All Numbers are forced to live in the containment city of Manhattan where they work in factories and live in squalor. The Number System requires them to be tagged with numbers on their necks that drop as fifty more Numbers are executed each week using the chemical Agent-10, a chemical that strips Numbers of they're regenerative abilities and allows them to die. Indie Caserento is a seventeen year old Number living with her sister, Adrian, in Manhattan. Working for a band of thieves has made them wealthier than most Numbers, but still on a count down to their deaths. They think they have a few more years left until their numbers are up, but when Adrian steals from the Monitors both of their numbers are dropped to zero. Their deaths seem imminent until the government makes them an offer. An offer that could change the course of history.