At the age of 10, Fanny Price is sent to live with her wealthy uncle and aunt, Sir Thomas and Lady Bertram, as her own parents do not have enough money to support their many children. Once at Mansfield Park, Fanny meets her cousins Tom, Maria, Edmund, and Julia, as well as Fanny's other maternal aunt, Mrs Norris. Fanny does not feel welcome, and Norris treats her more like a servant than a relative. Edmund behaves kindly to her, and the two develop a friendship that grows as the years progress.
When Fanny is eighteen, Sir Thomas and his eldest son Tom travel to Antigua. In their absence, the Bertram family is disrupted by the arrival of Henry and Mary Crawford, relatives of the local clergyman. Worldly, cynical and beautiful, Mary and Henry arrive looking for amusement. Edmund is instantly smitten with Mary, somewhat ignoring and hurting Fanny. Maria and Julia both vie for Henry's affections, even though Maria is already engaged to Mr Rushworth. Henry shamelessly flirts with Maria. Later, Tom returns from Antigua, arriving drunk and bringing a friend, Mr Yates, with him. Yates and Tom convince the Bertrams and Crawfords to stage a risque play, Lovers' Vows. The play allows the young people to openly flirt with each other. Edmund initially speaks out against the play, but changes his mind when he is offered a part that allows him to act out flirtatious scenes with Mary. Sir Thomas arrives home, and in anger immediately stops the play.
Maria marries Rushworth, esteeming his fortune above his character. Henry decides to pursue Fanny as a means to amuse himself. However, Fanny's gentle and kind nature gradually captures his fancy, and Henry becomes emotionally attached to her. After his behaviour towards the Bertram girls, Fanny distrusts him and does not believe his declarations of love. Even so, Henry proposes and Fanny is pressured by her uncle to accept the offer; she disappoints the family by refusing. Angry, Sir Thomas gives Fanny an ultimatum – accept Henry's proposal of marriage or be sent back to her poor family and experience the difference in comfort. Fanny looks to Edmund for support, but his indifference forces her to choose the latter. Several days after her return home, Henry pays a visit to convince Fanny that his affections for her are genuine. Although she looks more favourably on him, Fanny continues to cling to her feelings for Edmund and rejects Henry. Only when a letter from Edmund arrives which discloses his hopes of marrying Mary does Fanny accept Henry's offer. However, Fanny realizes she does not trust him, and takes back her acceptance the next day. Henry leaves, exceedingly hurt and angry. Edmund arrives to take Fanny back to Mansfield Park to help care for Tom, who has fallen seriously ill and is near death. Edmund confesses he has missed Fanny.
Henry gains Maria's pity when she learns of Fanny's refusal of his marriage proposal, and together they succumb to their lust. The affair is discovered by Fanny and Edmund. Shocked, Fanny is comforted by Edmund and the two nearly kiss, but he remembers himself and pulls away. News of the scandal spreads rapidly and Mary quickly devises a plan to stifle the repercussions. She suggests that after a divorce, Maria would marry Henry while Edmund would marry Mary; together they might re-introduce Henry and Maria back into society. Fanny questions Mary as to how a clergyman could afford lavish parties, and Mary shocks everyone by stating that when Tom dies, Edmund will be heir to the family's fortune. Edmund is appalled and tells Mary that cheerfully condemning Tom to death whilst she plans to spend his money sends a chill to his heart. Having betrayed her true nature to the Bertram family, a shamed Mary leaves the Bertrams' company. Edmund ultimately declares his love for Fanny, and they marry. Sir Thomas gives up his plantation in Antigua and invests instead in tobacco, while Tom recovers from his illness. Fanny also mentions that her younger sister Susie has joined them at the Bertram household while Maria and Aunt Norris take up residence in a small cottage removed from Mansfield Park.
The film differs from the Jane Austen novel Mansfield Park in several ways. The film changes some central characters, eliminates several others, and reorganizes certain events. The result is a film that retains the core character evolution and series of events of Jane Austen's novel, but in other ways, some critics claim, stresses its themes and ideas differently. The plot changes the moral message of Austen's novel, and makes the story a critique of slavery rather than a conservative critique of the "modern"; in the novel Fanny's passivity and moral stance are seen as virtues but these aspects of her character are missing from the film, except during the staging of Lovers' Vows, from which she abstains.
Austen's novel mentions slavery on several occasions but does not elaborate on it. Most notably, in the novel, Fanny asks a question about the slave trade to Sir Thomas and is not answered. The film includes slavery as a central plot point, including explicit descriptions of the treatment of slaves (e.g. Fanny finds violent drawings of the treatment of slaves in Tom's room); numerous reminders of how Bertram family owes its wealth to slavery, as well as England's role in the slave trade.
The role and influence of slavery in the world of Mansfield Park is emphasized from the start of the film. Fanny sees a slave ship on her initial journey to the family, asks her coachman about it and receives an explanation. A parallel is drawn between Fanny's role as a woman and a poor relative in the Bertram family, and the role of slaves.
Tom Bertram's return from Antigua is motivated by his disgust with what he has seen there, and this disgust is reinforced by a journal that Fanny finds at Mansfield Park showing apparently criminal events occurring in Antigua that involve Sir Thomas.
At the end of the film a voiceover also informs the viewer that Sir Thomas has divested from his estates in Antigua, presumably as a form of redemption.
The character of Fanny is significantly different in the film. In the novel, Fanny is very shy and timid, and not accustomed to giving her own opinion. Her physical condition is frail, making her tire easily. In the film, in contrast, Fanny is extroverted, self-confident, and outspoken, while also being physically healthier. In addition, the film version of Fanny is portrayed as a writer from her childhood into her adulthood at Mansfield Park. These character traits are incorporated directly from the life of Jane Austen – some of Fanny's writings were written by Austen including the "History of England".
The film dispenses entirely with several characters, whilst changing the roles and character traits of others. The parson, Dr. Grant, and his wife and the Crawfords' half-sister, Mrs. Grant, do not feature in the film. Fanny's Royal Navy brother William visits Mansfield Park & gives Fanny an amber cross (continuing the trend to imbue Fanny with Jane Austen's life experience her naval brother Charles gave her an identical cross now to be seen at Jane Austen's House Museum). Her close relationship with William in the book is mostly replaced in the film by her relationship with her younger sister Susan, with whom in the novel, Fanny does not develop a relationship until her return to Portsmouth.
Fanny's banishment to Portsmouth is characterized as a punishment by a vengeful Sir Thomas rather than as a respite from stress following Henry Crawford's unwelcome attentions. In the novel, Fanny is never tempted to accept Mr. Crawford's proposals, whereas in the film, Fanny accepts, then repudiates, Henry Crawford's offer of marriage, and her family has full knowledge of it. (Presumably this is taken from events in the life of Jane Austen, who accepted a proposal of marriage from a man she had known since childhood, and then retracted her acceptance a day later.)
In the novel, Fanny remains at Portsmouth for several months, whereas in the film she returns to Mansfield Park much earlier in order to nurse Tom Bertram back to health. This makes her witness to the events that follow. In the film, Maria's adulterous liaison with Mr. Crawford occurs at Mansfield Park instead of in London; in the novel, Maria leaves her husband's house to run away with Crawford.
In the novel, the revelations of Maria's adulterous affair including Mary's casual attitude about it, occur through letters (including from Mary to Fanny); in the film the affair is carried on at Mansfield Park in full view of the family.
In the novel, the shock to the Mansfield family is increased by Julia Bertram's elopement with Mr. Yates; in the film Julia remains at home, receiving a love letter from Yates at the end of the film, instead of eloping with Mr. Yates.
Mansfield Park has received generally favorable reviews from critics. Film review aggregator Rotten Tomatoes reports that 76% of critics gave the film a positive review based on 68 reviews, with an average score of 6.9/10. On Metacritic, which assigns a rating out of 100 based on reviews from critics, the film has a score of 71 based on 31 reviews.
Roger Ebert of the Chicago Sun-Times gave it a four-star review, saying, "This is an uncommonly intelligent film, smart and amusing too, and anyone who thinks it is not faithful to Austen doesn't know the author but only her plots." Owen Gleiberman of Entertainment Weekly also gave the film a positive review, dubbing it as "a handsome and forceful piece of work" and praising O'Connor's ability to display the "quiet battle of emotions in Fanny."
Andrew Johnston (critic) of Time Out New York wrote: "Grafting incidents gleaned from Jane Austen's journals and letters onto the story of the author's third novel, Rozema captures the writer's combination of prickly wit and hopeless romanticism as few filmmakers have. ... You may be able to see Mansfield Park 's ending coming from a mile away, but it's so beautifully constructed and dramatically satisfying when it arrives that you probably won't mind at all."