After years as a widower, village doctor Mr Gibson has decided to remarry - something for which his naive daughter, Molly, is wholly unprepared. Soon Molly's world is overturned by the arrival of an unwanted stepmother and a bewitching and beautiful stepsister, Cynthia. In spite of their differences, the two girls quickly form a close relationship. The strength of this friendship is soon tested however, when the girls become rivals in love...and matters are further complicated when a dangerous secret emerges from Cynthia's past...with serious consequences for them both.