When Among the Hidden opens, our main man Luke is getting put under some hardcore house arrest. Turns out the Big Bad Government is cutting down the Garner's woods in order to build some mansions, which means that Luke is no longer going to have all the nice protective greenery to keep him from being seen. And hiding Luke is priority numero uno for the Garner family since he's an illegal third child. It seems that families in this dystopian future are only allowed to have two children—with serious consequences for breaking the law.
Now Luke is stuck hiding in his room slash the attic, with a vent as his only window to the outside world. Not a lot to work with, but our clever hero finds a way. He spies on the mansion construction of the houses and eventually peeps on the families that move in.
When Luke's mom heads back to work to help out with the family expenses, Luke is completely left on his own. Naturally, for any child, this spells mischief—mischief like doing chores and baking bread and basically just roaming about the house not hiding in the attic. Everything is going swimmingly until his father comes home and banishes Luke to his room. But it's not all doom and gloom: once he's back locked up in the attic, Luke sees a face in the neighbor's window.
A face that's not supposed to be there.
After spying on the neighbor's house for days, Luke eventually concludes that they have a third child, too. Woohoo! Well, except that Luke can't do a thing about it since he's not allowed to leave his room, let alone his house.
Of course, he has plenty of time to think and plan, and eventually he has a pretty good plan and the day comes when he puts that plan into action. Luke sneaks over to the neighbor's house. However a huge wrench is thrown into his plan and he finds out that the house is locked. (Gee, didn't plan for that?) Thinking on his feet, Luke breaks in, because duh. And this is when he meets that face in the window: Jen Talbot.
Jen not only introduces Luke to the life of a fancy-pants Baron, i.e. elite (fun-filled with chips and soda and using the internet, which sounds just like our everyday life!) but she also lets him in on her secret plans of a rally to overturn the Population Law that makes third children illegal. Luke—not being a Baron—really isn't keen on joining in, but Jen loads him up with some required reading to fill him in on how Government is controlling and suppressing the people.
Jen is all full steam ahead with the rally and enlisting her fellow shadow children through an online chat room, but Luke is getting cold feet. That's not the kind of negativity that Jen likes, so she kicks him out of her house. Ouch.
However, Jen sneaks into Luke's house the night before the rally to say goodbye. After some apologies, Luke says he'll see her when she comes back. And with that, we learn that Luke has never heard of foreshadowing. The next morning, Luke hears nothing about the rally. Total silence, for an entire week.
So, Luke sneaks over the Jen's house and snoops around until a man shows up waving a gun at him. But it's cool: turns out the man is Jen's dad, and they have a little heart-to-heart about Jen who, Mr. Talbot informs Luke, died at the rally. Wha???
Pretty soon, some Population Police crash their little meet-and-greet. Jen's dad ushers them out while Luke hides in the closet. Once they're gone, Mr. Talbot convinces Luke to gets a fake ID and flees the farm. Luke thinks it over for what seems like 2.7 seconds and agrees. (Well, it does sound better than an attic.)
Time for Luke, er, we mean Lee, to say goodbye to his family. He's off to live a new Baron life, complete with getting shipped off to boarding school. With Mr. Talbot as his personal chauffer, Luke takes a few glances back at his old home before turning around to see what lies ahead of Lee Grant.