Rosina da Silva (Driver) is a young Jewish woman living in 1840s London. After her doting father dies, she changes her name to Mary Blackchurch in order to pass herself off as a Gentile and secure a position as a governess. Rosina then gets a job with the Cavendish family in remote Scotland, with her charges being randy teenager Henry (Rhys Meyers) and spoiled brat Clementina (Hoath). Her free-spirit entrances stodgy father Charles (Wilkinson), whom she aids in his obsession with the new art of photography. Where there's a dark room and chemistry, more than photos are bound to develop; and soon Mr. Cavendish comes up with a fixation of his own. Starts as a depiction of a woman adapting to different surroundings, but ends up like a history of the first girlie photos. In the end, her Jewishness isn't that big of a deal, leaving that portion of the story a dead end.