Shadow children

In a future where the Population Police enforce the law limiting a family to only two children, Luke has lived all his twelve years in isolation and fear on his family's farm, until another "third" convinces him that the government is wrong.

In the third installment of Haddix's series about a futuristic society in which families are forbidden to have more than two children, Nina, a secondary character in Among the Impostors, is falsely accused of treason and imprisoned by the Population Police. Her interrogator gives her an ultimatum: either she can get three other child prisoners, illegal third-borns like Nina, to reveal who harbored them and where they got their fake identification...

Trey may have saved Luke's life, but he still thinks of himself as a coward who can barely stand to be outdoors. Now Trey finds out Luke has been taken prisoner at Population Police headquarters. Trey is terrified, but he knows that if he doesn't rescue his friend, no one will. At police headquarters, Trey impersonates an officer to try getting to Luke. But just when it looks like he's close, Trey suddenly finds himself in danger of exposing not just...

When thirteen-year-old Luke Garner unwittingly sets off a rebellion which sweeps the country and ousts the Population Police from power, he quickly realizes that the new regime is corrupt and he may hold the only key to true freedom.