By Piya Sinha-Roy
October 15, 2018 at 04:00 PM EDT

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“It’s a climax in many different ways because it’s one that is a revelation for Harry, in which he discovers this inner strength that he was not aware of,” says Alfonso Cuarón of the denouement of Harry Potter and the Prisoner of Azkaban.

Cuarón stepped behind the camera to direct the 2004 film, which followed Harry’s third year at Hogwarts and told a deeper, darker story in J.K. Rowling’s wizarding world, complete with werewolves, time travel, and (how could anyone forget?) the chilling Dementors. Azkaban‘s pivotal scene sees Harry (Daniel Radcliffe) forced to defend Sirius (Gary Oldman), Hermione (Emma Watson), and himself from a horde of the hooded creatures at the school’s Great Lake. Harry believes his dead father somehow returned to save them with a powerful stag-shaped Patronus, but we later learn that it was Harry himself who saved the day, with the help of Hermione’s Time Turner.

Watch the clip above to see the filmmaker discuss that stag-gering scene and his other experiences making the film.

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Harry Potter and the Prisoner of Azkaban

  • Movie
  • PG
  • 141 minutes
  • Alfonso Cuarón