Harry Potter and the Chamber of Secrets is a 2002 fantasy film directed by Chris Columbus and distributed by Warner Bros. It is the sequel to Harry Potter and the Philosopher's Stone. 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 30th 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 his first year at Hogwarts, Harry Potter spends the summer without receiving letters from his Hogwarts friends. In his room, Harry meets Dobby, a house-elf who warns him bad things will happen if he returns to Hogwarts, and let slip he intercepted his friends' letters. Harry chases him downstairs, where Dobby sabotages a cake and ruins a job promotion. The Dursleys lock Harry up, but Ron, Fred and George Weasley rescue him in their father's enchanted flying Ford Anglia.
The Weasley family has breakfast and Harry meets Ron's sister Ginny Weasley, who is fond of him, then they go to Diagon Alley via Floo Network fireplace, though Harry got lost and found by Hagrid. While buying school supplies they run into Hermione, and attend a book-signing by celebrity wizard Gilderoy Lockhart, who announces he will be the new Defence Against the Dark Arts teacher. Harry also encounters Draco and his father Lucius Malfoy, who slips a book in Ginny's cauldron. When Harry and Ron are blocked from entering Platform 9¾ (later revealed to be Dobby's doing), they fly to Hogwarts on the Ford Anglia and crash into the hostile Whomping Willow tree. Ron's wand is damaged, and the car throws them out before driving off into the Forbidden Forest. The Ford Anglia nearly exposed the existence of wizards to Muggles (non-magical civilians) that should have Harry and Ron expelled. They are allowed to attend school and face detention instead. Harry meets Colin Creevey who idolizes him and takes snapshots. Draco is recruited as new Seeker for Slytherin Quidditch team; insults Hermione for being Muggle-born. Harry managed to beat Draco in a tampered match.
While serving detention with Lockhart, Harry hears strange voices, later find spiders fleeing. Caretaker Argus Filch's cat, Mrs. Norris, is found petrified, and a message written in blood announcing the "Chamber of Secrets has been opened; Enemies of the Heir… beware." Professor Minerva McGonagall explains that one of Hogwarts' founders, Salazar Slytherin, supposedly constructed a secret Chamber and dwells inside it a monster that only his Heir can control, to purge the school of impure-blooded wizards and witches. More attacks occur over the course of the year. Justin Fletchley, Headless Nick, and Colin fall victim. Harry and Ron suspect Draco is the Heir, so Hermione suggests they question him while disguised using polyjuice potion. Their makeshift laboratory is in a disused girls' bathroom haunted by a ghost, Moaning Myrtle.
When Harry communicates with a snake in a duel set up by Snape and Lockhart, surprisingly learns he can speak Parseltongue something Salazar Slytherin could do, the school suspects him as the Heir. On Christmas, Harry and Ron disguising themselves as Gregory Goyle and Vincent Crabbe; learn Draco is not the Heir, but he mentions that a girl died when the Chamber was last opened fifty years ago. Harry finds an enchanted diary in the bathroom, owned by a former student named Tom Riddle, which shows him a flashback to fifty years before, where Riddle accused Hagrid, then a student, of opening the Chamber. When the diary disappears and Hermione is petrified, Harry and Ron question Hagrid. Dumbledore, Ministry of Magic Cornelius Fudge, and Lucius come to take Hagrid to Azkaban prison. Lucius has Dumbledore suspended. Hagrid discreetly tells the boys to "follow the spiders." In the Forbidden Forest, Harry and Ron find Aragog, a giant spider who confirms Hagrid's innocence and that the dead girl was found in a bathroom. Aragog then sets his colony of Acromantula on the boys, but the now-wild Ford Anglia saves them.
A book page found in Hermione's hand from when she was in the library, identifies the monster is a basilisk, a giant serpent that instantly kills those who make direct eye contact with it, and the petrified victims saw it indirectly. The school staff learns Ginny was taken into the Chamber, and are convince Lockhart has what it takes to save her. Harry and Ron went and caught Lockhart planning to flee. It turns out Lockhart is a fraud: he used memory-erasing charms on witches and wizards to take credit for their accomplishments. They drag him to Myrtle's bathroom, knowing Myrtle was the girl the Basilisk killed, and unravel the Chamber's entrance. Once inside, Lockhart uses Ron's damaged wand against them, it backfires, wiping his memory, and causes a cave-in.
Harry enters the Chamber alone and finds Ginny unconscious and dying, guarded by Riddle. He reveals his full name, Tom Marvolo Riddle, from which he created the anagram for his new identity, "I am Lord Voldemort". Harry realizes Riddle is the Heir and Voldemort's 16-year-old self. He used the diary to manipulate Ginny and reopen the Chamber. Riddle grudgingly tells after the Chamber was last opened, Dumbledore kept a close watch on him that he decided to preserve his 16-year-old self in a diary, in case something were happen to him; eventually reopen the Chamber and continue his work specifically when learning how Harry inadvertently defeated his future self. Once Ginny does die, Riddle will use her life force to be reborn as Voldemort himself. After Harry expresses support for Dumbledore, Dumbledore's Fawkes flies in with the Sorting Hat, and Riddle summons the Basilisk. Fawkes blinds the Basilisk, and the Sorting Hat ultimately produces a sword with which Harry battles and slays the Basilisk, but he is poisoned by its fangs.
Harry destroys Riddle's soul and revives Ginny by stabbing the diary with a basilisk fang. Fawkes' tears heal Harry, and he returns to Hogwarts with his friends and a baffled Lockhart. Dumbledore, reinstated as headmaster, praises them and orders for Hagrid's release. Harry, troubled by similarities to Riddle, Dumbledore theorize that Voldemort unintentionally transferred some of his powers to Harry the night he gave him the scar, explaining his ability to speak Parseltongue. Dumbledore shows Harry that the sword he wielded is Godric Gryffindor's own sword, and says he is different from Voldemort because he chose Gryffindor instead of Slytherin. Harry accuses Lucius, Dobby's master, of putting the diary in Ginny's cauldron and tricks him into freeing Dobby. The Basilisk's victims are healed thanks to Professor Sprout and rejoice. Hermione reunites with Harry and Ron, and Hagrid returns.
In a post-credits scene, a new Gilderoy Lockhart book is on display at Flourish & Blotts, entitled "WHO AM I?" and depicting an amnesiac, confused Lockhart in a straitjacket.