Cooney continues her mastery of suspense with this story about a screw-up rich kid and bio-terrorism. Sixteen-year old Mitty cares about nothing but music and Olivia, the school’s ace scholar. Mitty deliberately blows off school, until he’s forced to start a paper for his biology class. He finds an old medical book and in it, an envelope containing two scabs from a 1902 smallpox epidemic. He crumbles one, and inhales the dust from it. Then Mitty begins to learn about the horrors of smallpox, and realizes that he may have exposed himself. Terrified not only of getting the disease, but also of starting another epidemic, Mitty keeps his secret until he can’t escape the fact that somehow he must become a real hero. Punctuating the drama with plenty of humor, Cooney builds the suspense and keeps it going for another teen-pleaser that’s hard to put down. (Fiction. 12-14)