Jules Daly becomes the legal guardian of her niece Maddie and nephew Milo after the loss of her sister and brother-in-law. Maddie is a fun-loving girl and Milo is a rebel and troublemaking teenager. After Jules gets laid off at work inBuffalo, New York and the children's nanny quits following Maddie's pranks, Jules reprimands Maddie for driving the nanny away and grounds Milo for sneaking out and shoplifting a game. Paisley Winterbottom, the butler of the children's wealthy grandfather Duke Edward, appears with an invitation for Milo and Maddie to spend the Christmas holidays with his employer in the country of Castlebury. Jules initially refuses, but decides to go for the children's sake. Arriving at the palace, Jules finds herself meeting Ashton, the brother of her sister's husband, and finds herself falling in love. Looking around, she finds no Christmas trees and asks the Duke why there isn't any. He replies he doesn't like them. Jules, however, takes Maddie out to get a tree and then they all decorate it. Edward finds out and becomes furious until Maddie hands him an ornament, which turns out to be the same one his brother had given him when they were children. Finally appreciating the spirit of the season, he tells Paisley to send invitations out for a Christmas Eve ball. Overhearing Ashton and Edward speaking disapprovingly of someone "untitled" and "crass" they'd rather not invite to the ball, Jules mistakenly believes it to be about her. Though they are actually talking about someone else. When the staff accidentally burns Jules' dress, she takes this as an excuse not to attend. Jules, feeling unwelcome, decides to go back to the USA early only telling the children. Despite their efforts to make her stay, she leaves, asking them not to tell anyone until she is gone. Mrs. Birch, the housekeeper, finds that Jules is missing, so she leads the staff to retrieve her from the train station while also having a dress brought in from Vienna. Meanwhile at the ball, Ashton verifies his girlfriend Lady Arabella only wants him for his title while also clearing up the fact that the woman they talked bad about was an "awful grizzly woman" named Bunny McCracken who hates children. Jules arrives at the ball. When Ashton finds her, she says she is trying to not be an embarrassment. Confused, he asks for an explanation. From Jules' mistakenly interpreted eavesdropping, Ashton clears things up, and then they dance. Arabella and her parents unsuccessfully attempt to turn Edward and Ashton against Jules, then storm out. Ashton asks Jules to extend their stay and she agrees. The family then goes and "catches Santa" putting gifts under the Christmas tree. Some time later, Jules and Ashton are married, and their friends and family watch as they ride off in a coach together.
In August 2008, writer and director Michael Damian told OK Magazine that he was "working on a screenplay called Christmas At Castlebury Hall". The film was shot at Peleş Castle, Stirbei Castle, the Bragadiru Palace and at MediaPro Studios in Bucharest, Romania February and March 2011. The film's cinematographer is Viorel Sergovici. On July 16, Michael Damian announced the film's new name: A Princess for Christmas.
