Mike Fowler thinks the small desert town of Ambrosia is a dry, forsaken blip on the edge of civilization. He has no friends, no fun, and no answers to the agonizing disappearance of his dad in a top-secret military mission. But that could all change after Mike stumbles onto his dad's puzzling journal in the old B-17 out back. The mysterious entries in the journal lead him to a hidden canyon! Something big--maybe a covert military operation--is going on in that secluded canyon. And Mike is sure if he just follows the clues, he'll find his dad. But with each new discovery, he and his daring companions, Ben, Spence, and Winnie, land in more and more danger.