内容简介：
"If I had the ability to stop one of the most insidious plots since 9/11, would I? Would I risk everything, even my own life and the safety of my family members?" Teenagers Samantha Marie Li Vinte and her best friend Danny Zimmer live in Castle Hedge, a typical small town in southern Ohio where not much of anything ever happens. But their lives are about to be forever changed when Sam inadvertently discovers that a terrorist organization has installed a sleeper cell operative disguised as a substitute teacher at their school. Mr. Sainclair, who teaches computer design, murdered Sam's past instructor, and is now using his job to sneak illegal drugs into the country and plot a terrorist attack. It seems Sainclair has found the perfect cover. After all, who would think that a mildmannered computer teacher is a drug-dealing terrorist? When Sam and Danny come forward with their seemingly outlandish accusations, will they be able to convince their families of the danger that lies ahead? Faced with relentless attacks by Sainclair and his hired mercenaries, Sam and Danny struggle to survive the week-and quite possibly, save the country.