If you find yourself contemplating writing a series, then I recommend reading FOUND with a writer's eye. Ms. Peterson starts with a Prologue: An airline employee finds an airplane full of babies, and then the airplane vanishes. The employee is told to never speak of what happened again.
The story picks up thirteen years later, with friends Chip and Jonah. Both are adopted, and each of them receives a mysterious letter. It says, YOU ARE ONE OF THE MISSING. See the series potential? Ms. Peterson can create a story for each child that was on the plane.
Chip and Jonah set out to solve the mystery, aided by Jonah's sister, Katherine. They discover a vast conspiracy that involves time travel. School Library Journal says, "Haddix's latest science fiction series starts off with a bang in this nail-biter...It will leave readers on the edge of their seats and begging for more."
On the very last page of FOUND, the kids find themselves transported to the fifteenth century. Luckily, the publisher whets our appetites, and provides a sneak peek at the next book in the series. It's called, THE MISSING, BOOK 2, SENT.