Emma Watson through out Harry Potter Series

Harry potter and the Sorcerer's Stone

• Emma Watson played Hermione Granger, Harry's other best friend. Watson's Oxford theatre teacher passed her name on to the casting agents and she had to do over five interviews before she got the part. Watson took her audition seriously, but "never really thought [she] had any chance of getting the role." The producers were impressed by Watson's self-confidence and she outperformed the thousands of other girls who had applied.
• Hermione first appears in Philosopher's Stone when she meets future companions Harry and Ron on the Hogwarts Express. She constantly annoys her peers with her knowledge. Harry and Ron initially consider her arrogant, especially after she criticises Ron's incantation of the Levitation Charm. They heartily dislike her until they rescue her from a troll, for which she is so thankful that she lies to protect them from punishment, and their friendship begins. Hermione's knack for logic later enables the trio to solve a puzzle essential to retrieving the Philosopher's Stone, and she defeats the constrictive Devil's Snare plant by summoning a "jet of bluebell flame" - the same spell she had used earlier in the story on Snape.
  Rowling said on her website that she resisted her editor's requests to remove the troll scene. "Hermione is so very annoying in the early part of Philosopher's Stone that I really felt it needed something (literally) huge to bring her together with Harry and Ron."

Harry Potter and the Chambers of Secrets

• Hermione (along with most of the female students at Hogwarts) develops a crush on handsome new Defence Against the Dark Arts teacher Gilderoy Lockhart in Harry Potter and the Chamber of Secrets. During a morning confrontation between the Gryffindor and Slytherin Quidditch teams, a brawl nearly ensues after Draco Malfoy calls her a "Mudblood," an insulting epithet for Muggle-born wizards of which she does not understand yet and later ignores. She assembles the Polyjuice Potion needed for the trio to disguise themselves as Malfoy's housemates to collect information about the Heir of Slytherin who has reopened the Chamber of Secrets. However, she is unable to join Harry and Ron in the investigation after the hair plucked from the robes of Slytherin student Millicent Bulstrode (with whom Hermione was previously matched up during Lockhart's ill-fated Duelling Club) was that of her cat, whose appearance she takes on in her human form; it takes several weeks for the effects to completely wear off. After the first Quidditch match, she destroys a rogue Bludger bewitched by Dobby the house-elf to save Harry's life. Hermione is Petrified by the basilisk after successfully identifying the creature through library research. Though she lies incapacitated in the hospital wing, her information is crucial to Harry and Ron in their successful mission to solve the mystery of the Chamber of Secrets. Hermione is revived after Harry kills the basilisk, but she is devastated to learn that all end-of-year exams have been cancelled as a school treat.

Harry Potter and the Prisoner of Azkaban

• Hermione buys a cat named Crookshanks, who takes to chasing Ron's pet rat, Scabbers. Before the start of term, Professor McGonagall secretly gives her a Time-Turner, a device which enables her to go back in time and handle her heavy class schedule, though this is not revealed until the penultimate chapter. Much tension comes into play between Hermione and her two best friends; Harry is furious with her because she told McGonagall that he had received a Firebolt, which was confiscated to be inspected for traces of dark magic. Ron is angry because he feels Crookshanks is responsible for Scabbers' disappearance, while Hermionie fiercely maintains that Crookshanks is innocent. While filling in for Remus Lupin in one Defence Against the Dark Arts class, Severus Snape labels Hermione "an insufferable know-it-all" and penalises Gryffindor after she speaks out of turn in her attempt to describe a werewolf when no one else does. She correctly deduces Lupin's secret after completing Snape's homework assignment from the class, while Crookshanks proves vital in exposing Scabbers as Peter Pettigrew, a friend of James and Lily Potter who revealed their whereabouts to Lord Voldemort the night of their murders, and was able to wrongly implicate Sirius Black (revealed to be Harry's godfather) in the Potters' deaths. The Time-Turner enables Hermione and Harry to rescue Sirius and the hippogriffBuckbeak

Harry Potter and the Goblet of Fire

• Hermione is horrified by the cruelty she witnesses to house-elves and founds S.P.E.W., the Society for the Promotion of Elfish Welfare, as an effort to gain basic rights for the elves. She is Bulgarian Quidditch prodigy Viktor Krum's date at the Yule Ball in Goblet of Fire. The proper pronunciation of her name (Her-my-oh-nee) is interjected into the plot when she teaches it to Krum; the best he can do is "Herm-own-ninny," but she has no problem with it. She later gets into a heated argument with Ron after he accuses her of "fraternising with the enemy"in reference to her friendship with Krum. In the book, it hinted that Hermione had feelings for Ron when saying that Ron couldn't see her like a girl and Krum could. She supports Harry through the Triwizard Tournament, helping him prepare for each task. At the end of the second task, she was asked by Krum to come to Bulgaria with him. She politely refused and Krum was only a friend. It is unknown if Krum and Hermione kissed as mentioned in the sixth book. Near the end of the term she stops fraudulent tabloid reporter and unregistered AnimagusRita Skeeter, who had published defamatory material about Hermione, Harry, and Hagrid during the Triwizard Tournament, by holding her Animagus form (a beetle) captive in a jar.

Harry Potter and the Order of the Phoenix

• Hermione becomes a Gryffindor prefect along with Ron, and befriends Luna Lovegood, but their friendship gets off to a rocky start after Hermione chastises the publication of Luna's father: "The Quibbler's rubbish, everyone knows that." She also lambasts housemate Lavender Brown for believing the Daily Prophet's allegations of Harry fabricating stories of Voldemort's return. Also, Ron and Hermione continue spending their time bickering like a married couple, but they show much more loyalty to Harry. Later, with Luna's assistance, Hermione blackmails Rita Skeeter into interviewing Harry for an upcoming issue of The Quibbler. Attempts to ban the magazine from Hogwarts are futile as the story spreads quickly through the school. One turning point in the series is when she conceives the idea of Harry secretly teaching defensive magic to a small band of students in defiance of the Ministry of Magic's dictum to teach only the subject's basic principles. Hermione gets an unexpectedly huge response, and the group becomes the nascent Dumbledore's Army. She is involved in the battle in the Department of Mysteries and seriously injured by Death Eater Antonin Dolohov, but makes a full recovery.

Harry Potter and the Half-Blood Prince

• New Advanced Potions professor Horace Slughorn invites Hermione to join his "Slug Club," and she helps Ron retain his spot on the Gryffindor Quidditch team when she secretly jinxes Cormac McLaggen, causing him to miss his last save attempt during Keeper tryouts. Hermione's feelings for Ron continue to grow and she decides to make a move by inviting him to Slughorn's Christmas Party, but he romances Lavender instead in retaliation for Hermione having kissed Krum. She attempts to retaliate by dating McLaggen at the Christmas party, but her plan goes bust and she abandons him midway through the party. Ron and Hermione continually feud, (Ron is upset with her because she set birds to attack him after seeing him and Lavender Brown kissing, Hermione is mostly mad because of her growing jealousy) with each other until he suffers a near-fatal poisoning from tainted mead, which frightens her enough to reconcile with him. Following Dumbledore's death, Ron and Hermione both vow to stay by Harry's side regardless of what happens. A minor subplot in the book is that Hermione and Harry form a rivalry in Potions, as Hermione is used to coming first in her subjects and is angered that Harry outperforms her undeservingly by following tips and different instructions written in the margins of Harry's potions book by the previous owner. Hermione is also the only one of the trio to successfully pass her Apparition test (Ron barely failed and Harry was too young).