The Greystones and their doubles, the Gustanos, must team up to save the alternate world, before both worlds are lost.

Chess has always been the protector over his younger siblings, Emma and Finn. They have been a happy family, just the three of them and their mom

After crossing five continents and solving some of history's most perplexing mysteries, Amy and Dan Cahill are nearing the end of their adventure

Many surprises await twelve-year-old Edwy Watanaboneset when the Freds return him to Cursed Town, including that he has siblings in Refuge City w

Until their mother vanished, the Greystone kids, Chess, Emma, and Finn, knew nothing about the other world. Everything is different there. It's a

Chess has always been the protector over his younger siblings, Emma and Finn. They have been a happy family, just the three of them and their mom

Throughout the hunt for the 39 Clues, Amy and Dan Cahill have uncovered history's greatest mysteries and their family's deadliest secrets. But ar

Throughout the hunt for the 39 Clues, Amy and Dan Cahill have uncovered history's greatest mysteries and their family's deadliest secrets. But ar

Told from separate viewpoints, as Finn, Emma, and Chess Greystone and Natalie Mayhew, ages eight to thirteen, continue their quest to rescue thei

Jonah was able to save all of time from collapsing but in doing so gained a twin brother, Jordan, who must learn what has happened and do his own

Twelve-year-old twins Nick and Eryn investigate why their mother and new stepfather are keeping secrets, why they are forbidden to meet their ste

Since the Enforcers raided Refuge City, Rosi, Edwy, and the others are captured and forced to work as slave labor on an alien planet, digging up