When a ship sinks, one-year-old Sophie is found floating in a cello case in the English Channel. She is saved by a passenger, Charles Maxwell. Sophie spends her first twelve years with Charles as he reads Shakespeare aloud to her, feeds her meals on an open atlas, and lets her wear pants. In her 19th century world, the National Childcare Agency decides that Charles is an unfit guardian. Sophie and Charles escape to Paris to search for her mother, and Sophie begins an adventure set mostly on the rooftops of Paris with an amazing gang of street kids who help her on her quest.