When the Rev. Joseph Carey dies from fever, his daughter Isabelle has to leave the rectory in Cumberland where she was born. She goes to London to work as a scullery maid in the London home of Philip Ashleigh, Master of Mallersby. But when Mr. Ashleigh learns her true identity, he sends her to Mallersby, his country home, as governess to his young daughter, Christina. There, Isabelle finds that the master is becoming the most important person in her life.