If you haven't read the book, or seen one of the several film adaptations, here's a quick overview of the plot.
(The following plot overview is mainly taken from http://www.sparknotes.com/lit/pride/summary.html, with some additions of my own. Also note, this summary more closely resembles the plot of the BBC production than the book.)
The news that a wealthy young gentleman named Charles Bingley has rented the manor of Netherfield causes a great stir in the nearby village of Merryton, especially in the Bennet household at the manor of Longbourn. The Bennets have five unmarried daughters--from oldest to youngest, Jane, Elizabeth, Mary, Kitty, and Lydia --and Mrs. Bennet is desperate to see them all married. The Bennets attend a ball at which Mr. Bingley is present. He is taken with Jane and spends much of the evening dancing with her. His close friend, Mr. Darcy, is less pleased with the evening and haughtily refuses to dance with Elizabeth, which makes everyone view him as arrogant and obnoxious.
At social functions over subsequent weeks, however, Mr. Darcy finds himself increasingly attracted to Elizabeth's charm and intelligence. Jane's friendship with Mr. Bingley also continues to burgeon, and Jane pays a visit to the Bingley mansion. On her journey to the house she is caught in a downpour and catches ill, forcing her to stay at Netherfield for several days. In order to tend to Jane, Elizabeth hikes through muddy fields and arrives with a spattered dress, much to the disdain of the snobbish Miss Bingley, Charles Bingley's sister. Miss Bingley's spite only increases when she notices that Darcy, whom she is pursuing, pays quite a bit of attention to Elizabeth.
When Elizabeth and Jane return home, they find their cousin, Mr. Collins, visiting at Longbourn. Mr. Collins is a young clergyman who stands to inherit Mr. Bennet's property, which has been "entailed," meaning that it can only be passed down to male heirs. Mr. Collins is a pompous fool, though he is quite enthralled by the Bennet girls. Shortly after his arrival, he makes a proposal of marriage to Elizabeth. However, because she and her sister Jane have decided that they should like to marry only for love, she turns him down, wounding his pride. Meanwhile, the Bennet sisters have become friendly with militia officers stationed in Merryton. Among them is Wickham, a handsome young soldier who is friendly toward Elizabeth and tells her how Darcy cruelly cheated him out of an inheritance.
At the beginning of winter, the Bingleys and Darcy leave Netherfield and return to London, much to Jane's dismay. A further shock arrives with the news that Mr. Collins has become engaged to Charlotte Lucas, Elizabeth's best friend and the daughter of a local nobleman, Sir William Lucas. Charlotte explains to Elizabeth that she is getting older and needs the match for financial reasons. Charlotte and Mr. Collins get married and Elizabeth promises to visit them at their new home. As winter progresses, Jane visits her Aunt and Uncle Gardiner's family in London (hoping also that she might see Mr. Bingley). However, Miss Bingley visits her and behaves rudely, while Mr. Bingley fails to visit her at all. The marriage prospects for the Bennet girls appear bleak.
That spring, Elizabeth visits Charlotte, who now lives in Kent, near Rosings, the home of Mr. Collins's patron, Lady Catherine de Bourgh, who is also Darcy's aunt. Darcy calls on Lady Catherine and encounters Elizabeth, whose presence leads him to make a number of visits to the Collins's home, where she is staying. One day, he makes a shocking and extremely ungentlemanlike proposal of marriage, which Elizabeth quickly refuses. She tells Darcy that she considers him arrogant and unpleasant, then scolds him for steering Bingley away from Jane and disinheriting Wickham. Darcy leaves her but shortly thereafter delivers a letter to her. In this letter, he admits that he urged Bingley to distance himself from Jane, but claims he did so only because he thought their romance was not serious. As for Wickham, he informs Elizabeth that the young officer is a liar and that the real cause of their disagreement was Wickham's attempt to elope with his young sister and ward, Georgiana Darcy.
This letter causes Elizabeth to reevaluate her feelings about Darcy. She returns home and acts coldly toward Wickham. The militia is leaving town, which makes the younger, rather man-crazy, Bennet girls distraught. Lydia manages to obtain permission from her father, despite Elizabeth's protests (she doesn't reveal Wickham's true nature to her father), to spend the summer with Col. Forrester and his wife in Brighton, where Wickham's regiment will be stationed.
In June, Elizabeth takes a trip into Derbyshire with her Aunt and Uncle Gardiner. The trip eventually takes her to Lambton, a town near Pemberley, which is Darcy's estate. She visits Pemberley, after making sure that Darcy is away, and delights in the building and grounds, while hearing from Darcy's servants that he is a wonderful, generous master. Suddenly, Darcy arrives and behaves cordially toward her. Making no mention of his proposal, he entertains the Gardiners and invites Elizabeth to meet his sister.
Shortly thereafter, however, a letter arrives from home, telling Elizabeth that Lydia has eloped with Wickham and that the couple is nowhere to be found, which suggests that they may be living together out of wedlock. Fearful of the disgrace such a situation would bring on her entire family, Elizabeth hastens home, after revealing the secret to Darcy, and convincing herself that she shall never have the chance to get to know Darcy better, now that she has realizes that she has fallen in love with him. He, however, hastens to London to track down the wayward couple, unbeknownst to anyone else. Mr. Gardiner and Mr. Bennet also go off to search for Lydia, but Mr. Bennet eventually returns home empty-handed. Just when all hope seems lost, a letter comes from Mr. Gardiner saying that the couple has been found and that Wickham has agreed to marry Lydia in exchange for an annual income. The Bennets are convinced that Mr. Gardiner has paid off Wickham, but Elizabeth learns secretly via correspondence from her Aunt Gardiner that the source of the money, and of her family's salvation, was none other than Darcy.
Now married, Wickham and Lydia return to Longbourn briefly, where Mr. Bennet treats them coldly. They then depart for Wickham's new assignment in the North of England. Shortly thereafter, Bingley returns to Netherfield and resumes his courtship of Jane. Darcy goes to stay with him and pays visits to the Bennets but makes no mention of his desire to marry Elizabeth. Darcy tells Bingley that Jane had been in London during he winter and apologizes for his part in keeping them separated. He then goes to London for a short time. While he is gone, Bingley proposes to Jane, to the delight of everyone but Bingley's haughty sister.
While the family celebrates, Lady Catherine de Bourgh pays a visit to Longbourn. She corners Elizabeth and says that she has heard that Darcy, her nephew, is planning to marry her. Since she considers a Bennet an unsuitable match for a Darcy, and insists that her own daughter is meant to become Darcy's wife, Lady Catherine demands that Elizabeth promise to refuse him. Elizabeth spiritedly refuses, saying she is not engaged to Darcy, but she will not promise anything against her own happiness.
When Darcy returns to Hertfordshire, he accompanies Bingley on a visit to Longbourn. Elizabeth and Darcy go out walking together and she thanks him for taking care of the matter with Lydia. He then tells her that his feelings have not altered since the spring while apologizing for his previous hurtful proposal. She tenderly accepts. Jane and Bingley and Elizabeth and Darcy are married in a double ceremony.
Interested in reading the original text by Jane Austen? Because the work is in the public domain, the complete text is available in several places on the internet. Here are two of them: an Annotated hypertext version of the novel at The Republic of Pemberley site, and the complete novel at Austen.com.
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