Thirteen-year-old Jonah is adopted. He has a natural-born ten-year-old sister, Katherine. He has always known he was adopted and his parents frequently tiptoe around him as if his emotions are about to fall apart.
Jonah and his friend Chip begin getting mysterious letters with no return address. They say things like, "You are one of the missing," and "They're coming back to get you."
Until now, Chip had no idea that he was also adopted. The idea seems to damage his usual clear thinking.
Katherine begins a quest to find out what is going on and drags the two boys along with her. They discover STRANGE things like stories about an appearing and disappearing airplane with 36 babies on it and no adults, people who seem to pop in and pop out of nowhere, and someone searching through their private stuff.
At a meeting for parents of adopted children, 36 teens are separated into a group and taken on a short field trip. They had no idea that the trip involved time and their real identities.
This book is the first in a series.