The Greystone Secrets Series by Margaret Peterson Haddix

What makes you you?The Greystone kids thought they knew. Chess has always been the protector over his younger siblings, Emma loves math, and Finn does what Finn does best—acting silly and being adored. They’ve been a happy family, just the three of them and their mom.But everything changes when reports of three kidnapped children reach the Greystone kids, and they’re shocked by the startling similarities between themselves and these complete strangers... moreWhat makes you you?The Greystone kids thought they knew. Chess has always been the protector over his younger siblings, Emma loves math, and Finn does what Finn does best—acting silly and being adored. They’ve been a happy family, just the three of them and their mom.But everything changes when reports of three kidnapped children reach the Greystone kids, and they’re shocked by the startling similarities between themselves and these complete strangers. The other kids share their same first and middle names. They’re the same ages. They even have identical birthdays. Who, exactly, are these strangers?Before Chess, Emma, and Finn can question their mom about it, she takes off on a sudden work trip and leaves them in the care of Ms. Morales and her daughter, Natalie. But puzzling clues left behind lead to complex codes, hidden rooms, and a dangerous secret that will turn their world upside down. less

Until their mother vanished, the Greystone kids—Chess, Emma, and Finn—knew nothing about the other world.Everything is different there. It’s a mirror image, except things are wrong. Evil. Their mother tried to fix it, but she and an ally got trapped there along with Ms. Morales, their friend Natalie’s mom.Now the four kids—brave Chess, smart Emma, kind Finn, and savvy Natalie—are determined to rescue everyone... moreUntil their mother vanished, the Greystone kids—Chess, Emma, and Finn—knew nothing about the other world.Everything is different there. It’s a mirror image, except things are wrong. Evil. Their mother tried to fix it, but she and an ally got trapped there along with Ms. Morales, their friend Natalie’s mom.Now the four kids—brave Chess, smart Emma, kind Finn, and savvy Natalie—are determined to rescue everyone.To do so, they have to go back: into the other world, where even telling the truth can be illegal.But in such a terrifying place, Chess doubts he can ever be brave enough. Despite all her brains, Emma can’t seem to break the code. With everything spiraling out of control, Finn has to pretend he’s okay.And for Natalie, the lies of the other world include some she wishes were actually true. What if she’s gotten so used to lying she no longer knows what to believe? less

In the conclusion to the Greystone Secrets series, the Greystones and their doubles, the Gustanos, must team up to save the alternate world—before both worlds are lost.As book three of the Greystone Secrets series opens, the Greystone kids have their mother back from the evil alternate world, and so does their friend Natalie. But no one believes the danger is past.Then mysterious coins begin falling from unexpected places... moreIn the conclusion to the Greystone Secrets series, the Greystones and their doubles, the Gustanos, must team up to save the alternate world—before both worlds are lost.As book three of the Greystone Secrets series opens, the Greystone kids have their mother back from the evil alternate world, and so does their friend Natalie. But no one believes the danger is past.Then mysterious coins begin falling from unexpected places. They are inscribed with codes that look just like what the Greystones’ father was working on before he died. And with the right touch, those symbols transform into words: PLEASE LISTEN. And FIND US, SEE US, HELP US. . . .The coins are messengers, telling the Greystones and their allies that their friends in the alternate world are under attack—and that the cruel, mind-controlling forces are now invading the better world, too.After another spinning, sliding journey across worlds, the Greystone kids must solve mysteries that have haunted them since the beginning: what happened when the Gustanos were kidnapped, what created the alternate world, and how a group of mismatched kids can triumph once and for all against an evil force that seems to have total control. less