Thirteen-year-old Lizzy Kennedy is not like the other girls in her town. She'd much rather be helping her doctor father with his patients than be stuck in frilly dresses and learn how to dance. This includes not poking your nose in other's people's business - but then the plague strikes and their beloved housekeeper, Jing, gets stuck in the Chinatown quarantine. Fear rules San Francisco... and Lizzy finds a strange boy hiding in Jing's room. The boy is called Noah. He says he's Jing's son. Is there really plague in San Francisco? Just what or who is the mysterious 'monkey' - and what has his secret got to do with anything?