Harry Potter and the Chamber of Secrets is a 2002 film directed by Chris Columbus and distributed by Warner Bros. Pictures. It is based on the novel of the same name by J. K. Rowling. The film, which is the second instalment in the Harry Potter film series, was written by Steve Kloves and produced by David Heyman. The story follows Harry Potter's second year at Hogwarts as the Heir of Salazar Slytherin opens the Chamber of Secrets, unleashing a deadly monster that petrifies the school's pupils. The film stars Daniel Radcliffe as Harry Potter, alongside Rupert Grint and Emma Watson as Harry's best friends Ron Weasley and Hermione Granger. It is the sequel to Harry Potter and the Philosopher's Stone and is followed by Harry Potter and the Prisoner of Azkaban.

It was released on 15 November 2002 in the United Kingdom and North America. The film was very well received at the box office, making US$879 million worldwide and is the 34th highest-grossing film of all time and the seventh highest-grossing film in the Harry Potter series. It was nominated for three BAFTA Film Awards in 2003.

After serving detention with Lockhart, Harry hears voices in the walls, and encounters a petrified Mrs. Norris, Argus Filch's cat, and a message written in blood announcing the Chamber of Secrets has been opened and enemies of "the heir, beware". Professor McGonagall explains one of Hogwarts' founder Salazar Slytherin hid a monster in the rumoured Chamber to purify the school of impure-blooded wizards and witches, and only his heir can control it. Harry suspects Malfoy to be the heir, so Hermione suggests using a Polyjuice Potion to disguise themselves as Malfoy's friends and ask him directly.

Hermione Jean Granger is a character in J.K. Rowling's Harry Potter series. She initially appears in the first novel, Harry Potter and the Philosopher's Stone, as a new student on her way to Hogwarts. After Harry and Ron save her from a mountain troll in the girls' toilets, she becomes close friends with them and often uses her quick wit, deft recall, and encyclopaedic knowledge to help them. Rowling has stated that Hermione resembles her at a younger age, with her insecurity and fear of failure.

Hermione Jean Granger is a Muggle-born Gryffindor student, and the best friend of Harry Potter and Ron Weasley. J.K. Rowling states that she was born on 19 September 1979 and she was nearly twelve when she first attended Hogwarts. She is an overachiever who excels academically, and is described by Rowling as a "very logical, upright and good" character. Rowling adds that Hermione's parents, two Muggle dentists, are a bit bemused by their odd daughter but very proud of her all the same." They are well aware of the wizarding world and have visited Diagon Alley with her. Rowling orignally planned for Hermione to have a sister, but the character never made an appearance in the novel and in 2004 Rowling noted that it "seemed too late" to introduce the character at that point. Rowling confirmed in a 2004 interview that Hermione is an only child.

Rowling claims the character of Hermione carries several autobiographical influences. "I did not set out to make Hermione like me but she is...she is an exaggeration of how I was when I was younger." She recalled being called a "little know-it-all" in her youth. Moreover, she states that not unlike herself, "there is a lot of insecurity and a great fear of failure" beneath Hermione's swottiness. Finally, according to Rowling, next to Albus Dumbledore, Hermione is the perfect expository character; because of her encyclopaedic knowledge, she can always be used as a plot dump to explain the Harry Potter universe. Rowling also claims that her feminist conscience is saved by Hermione, "who's the brightest character" and is a "very strong female character".

Hermione's name is derived from William Shakespeare's The Winter's Tale; Rowling claimed that she wanted it to be unusual since if fewer girls shared her name, fewer girls would get teased for it and it seemed that "a pair of professional dentists, who liked to prove how clever they are...gave [her] an unusual name that no-one could pronounce." Her original last name was "Puckle", but Rowling felt the name "did not suit her at all", and so the less frivolous Granger made it into the books.

Watson has said that Hermione is a character who makes "brain not beauty cool," and that though Hermione is "slightly socially inept," she is "not ashamed of herself." When filming Chamber of Secrets, Watson was "adamant" that she wasn't like Hermione, but she reflects that "as I got older, I realised she was the greatest role model a girl could have." In 2007, before the release of Order of the Phoenix, Watson said, "There are too many stupid girls in the media. Hermione's not scared to be clever. I think sometimes really smart girls dumb themselves down a bit, and that's bad. When I was nine or ten, I would get really upset when they tried to make me look geeky, but now I absolutely love it. I find it's so much pressure to be beautiful. Hermione doesn't care what she looks like. She's a complete tomboy."

Hermione is portrayed during the whole series as an exceptionally talented young witch. Rowling has stated that Hermione is a "borderline genius." She received ten O.W.L.s, which were nine Outstandings and one Exceeds Expectations. She is the best student in Harry's year and is repeatedly the first student to master any spell or charm introduced in classes and even from more advanced years, as evidenced when she is able to conjure a Protean Charm on the D.A.'s fake Galleon coins, which is actually a N.E.W.T. level charm. She is also the first one to be able to cast non-verbal spells. Hermione is an exceptional duellist, capable of outmatching even Death Eaters, as shown in the battle at the Department of Mysteries, at the Lovegoods' house, and in the Battle of Hogwarts. However, Rowling has stated that while during the first three books Hermione would have beaten Harry in a magical duel, by the fourth book Harry is so good at Defence Against the Dark Arts that he would have defeated Hermione. Hermione did not tend to do as well in subjects that were not learned through books or formal training, as broom flying did not come as naturally to her in her first year as it did to Harry, and she showed no affinity for Divination, which she dropped from her third year studies. She was also not good at Wizard's Chess, as it was the only thing at which she ever lost.

Hermione's Patronus is an otter, Rowling's favourite animal. Her wand is made of vine wood and dragon heartstring core; vine is the wood ascribed to Hermione's fictional birth month (September) on the Celtic calendar. Hermione is viewed by many as a feminist icon.

Emma Watson as Hermione Granger, Harry's other best friend and the trio's brains. 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.

Emma Charlotte Duerre Watson (born 15 April 1990) is an English actress and model. She rose to prominence playing Hermione Granger in the Harry Potter film series; she was cast as Hermione at the age of nine, having previously acted only in school plays. She starred in all eight Harry Potter films, alongside Daniel Radcliffe and Rupert Grint. Watson's work on the Harry Potter series has earned her several awards and more than 10 million. She made her modelling debut for Burberry's autumn/winter campaign in 2009. In October 2013, she was voted Sexiest Female Movie Star in a worldwide poll conducted by Empire magazine. In May 2014, BuzzFeed dubbed her the "most flawless woman of the decade".

In 2007, Watson announced her involvement in The Tale of Despereaux and the television adaptation of the novel Ballet Shoes, which was broadcast on 26 December 2007 to an audience of 5.2 million. The Tale of Despereaux, based on the novel by Kate DiCamillo, was released in 2008 and grossed more than US$86 million in worldwide sales. In 2012, she starred in Stephen Chbosky's film adaptation of The Perks of Being a Wallflower, and in 2014, she played Ila in Darren Aronofsky's biblical epic Noah.

Watson was appointed as a UN Women Goodwill Ambassador in 2014. She helped launch the UN Women campaign HeForShe, which calls for men to advocate for "gender equality".

In 1999, casting began for Harry Potter and the Philosopher's Stone (released as Harry Potter and the Sorcerer's Stone in the United States), the film adaptation of British author J. K. Rowling's best-selling novel. Casting agents found Watson through her Oxford theatre teacher, and producers were impressed by her confidence. After eight auditions, producer David Heyman told Watson and fellow applicants Daniel Radcliffe and Rupert Grint that they had been cast for the roles of the schoolfriends Hermione Granger, Harry Potter and Ron Weasley, respectively. Rowling supported Watson from her first screen test.