Harry Potter is having fun this summer. He can torment Dudley as much as he wants because the Dursleys are terrified what he might do to them. He's missing his friends though who haven't written to him and he's received nothing for his birthday but that's nothing new.

Harry is sent upstairs because the Dursleys are having a dinner party and here he finds on his bed Dobby, a house-elf who warns him terrible things are going to happen at Hogwarts and that he can't go back. Harry says he has to go to be with his friends even though they've ignored him all summer. Dobby tells Harry that he stole all of Harry's letters and Harry goes mad. He chases Dobby downstairs and Dobby ruins Aunt Petunia's pudding for the important guests, The Masons by using a Hover Charm.

Harry immediately receives a letter for under-age magic through owl post and the Mason's run off. The Dursleys now know that Harry can't use magic and lock him in his room with a cat flap on the door and the window locked with iron rails. They lock all of his magic equipment downstairs and Hedwig in her cage knowing that he can't escape. Things begin to look desperate for Harry until Ron, Fred and George arrive outside his bedroom window in a flying car in the middle of the night. Harry just manages to escapes before Uncle Vernon can pull him back.

They settle into term life well until when Harry, Hermione and Ron return from Nearly-Headless Nick's Deathday party they find Mrs. Norris' petrified body and a message about the Chamber of Secrets been opened. Harry has also started to here voices that nobody else can hear.

Lockhart sets up a duelling club and a snake appears out of Malfoy's wand when he was duelling with Harry. Harry tells it to leave and it does and everybody realises that Harry is a parelsmouth and presumes he is the heir of Slytherin who has unleashed the Chamber of Secrets!

Hermione, Ron and Harry create a Polyjuice potion to transfer into some Slytherin students to find out whether Malfoy is behind the opening of the Chamber, he isn’t. Hermione though gets cat hair mixed up in her potion and has to remain in the hospital wing for several months.

In Moaning Myrtle's bathroom Harry finds a secret diary. He learns the secret of the diary that it is Tom Riddle's and goes back to when the Chamber was first opened and discovers it was Hagrid who opened the Chamber of Secrets according to Riddle's memory.

They take the invisibility cloak and go to confront Hagrid but Cornelius Fudge arrives arresting Hagrid for the very same reason and they take him to Azkaban, the wizard prison. Lucius Malfoy arrives with a petition wanting Dumbledore to step down from headmaster, so he does, even though more and more people are been petrified such as Hermione.

The Chamber of Secrets takes its first victim, Ginny Weasley. Harry and Ron discover the entrance in their base, Moaning Myrtle's bathroom. Myrtle was the first ever victim of the Chamber of Secrets.

Harry gets to where Ginny is and here he discovers Tom Riddle who was the memory preserved in the diary but has taken over Ginny to be alive. Tom Riddle was the name of Lord Voldemort when he was a teenager. Harry has come to face Voldemort for the 3^rd time. Fawkes (Dumbledore's eagle) enters the Chamber with the Sorting Hat. Harry reaches in and finds a sword. He goes to kill the Basilisk's that Voldemort is controlling but the Basilisk's bites him. Fawkes heals Harry as phoenix's tears heal and Harry kills the diary by plunging the Basilisk's tooth into the diary and Ginny is saved.

Dumbledore returns and the Weasley's are in his office when Harry, Ron and Ginny enter. Harry tells the story but not that Ginny was been controlled by the diary.

Lucius Malfoy comes to the school with Dobby and Harry and Dumbledore realise it was Malfoy who placed the diary in Ginny's books during the fight at Flourish and Blotts. Harry gives the diary back to Lucius Malfoy with a sock over it. He throws the sock off and Dobby catches it and is set free. He has been rewarded for helping Harry.

They have a Hogwarts feast in their pyjamas and another year ends. The Mandrake potion cured all the petrified people and nobody had to do exams! Hagrid is release from Azkaban and Harry, Ron and Hermione find out that Percy has a girlfriend, Penelope Clearwater, a prefect from Ravenclaw.