When troubled sixteen-year-old Jimmer "JD" Dobbs returns from a mysterious summer "upstate" he finds that his mother has adopted an abused Rottweiler that JD names Johnny Rotten, but soon his tenuous relationship with the dog is threatened.

From the author of the Printz Honor Book "Airborn" comes an absorbing novel about a teenage boy whose parents bring home his new baby brother--a chimpanzee. In 1973, when a renowned Canadian behavioral psychologist pursues his latest research project--an experiment to determine whether chimpanzees can acquire advanced language skills--he brings home a baby chimp named Zan and asks his thirteen-year-old son to treat Zan like a little brother.