In Harry Potter and the Goblet of Fire, three schools compete in the Triwizard Tournament.
The participating schools are Hogwarts School of Witchcraft and Wizardry, Beauxbatons Academy of Magic and Durmstrang Institute. Each school is represented by a champion selected by the Goblet of Fire. Hogwarts champion Cedric Diggory is chosen first, but Harry’s name is unexpectedly selected as a fourth champion because the tournament has been secretly manipulated.
The three official tournament tasks test different abilities. Champions face a dragon, rescue people from the Black Lake and navigate a dangerous maze. The final task secretly becomes a trap when Harry and Cedric reach the Triwizard Cup, which has been turned into a Portkey.
The tournament’s name refers to the traditional competition among three wizarding schools, not to the number of champions in this particular film. Harry’s unexpected entry makes four competitors, which is a common source of confusion. The film’s ending also marks the return of Lord Voldemort and changes the series’ tone permanently.