Doctor Thorne adopts his niece Mary, keeping secret her illegitimate birth as he introduces her to the best local social circles. There she meets and falls in love with Frank Gresham - the heir to a vastly mortgaged estate and obliged to find a wealthy wife. Only Doctor Thorne knows that Mary is to inherit a large legacy that will make her acceptable to the otherwise disapproving middle-class society to which Frank belongs. Where fiery passion fails, understated English virtues of patience, persistence, and good humor prevail in this most appealing of Trollope's comedies.