"Goblet of Fire" is the fourth book in the Harry Potter series by J.K. Rowling. In this installment, Harry unexpectedly becomes a competitor in the Triwizard Tournament, a dangerous magical competition between three wizarding schools: Hogwarts, Beauxbatons, and Durmstrang. As the tournament progresses, Harry faces various challenges, including battling dragons and navigating a treacherous maze. The story also introduces significant themes, such as friendship, bravery, and the return of the dark wizard Voldemort, setting the stage for the conflicts in the subsequent books.