Remus Lupin: "So... The spell I am going to try and teach you is highly advanced magic, Harry — well beyond Ordinary Wizarding Level. It is called the Patronus Charm."
Harry Potter: "How does it work?"
Remus Lupin: "Well, when it works correctly, It conjures up a Patronus, which is a kind of anti-Dementor — a guardian that acts as a shield between you and the Dementor. The Patronus is a kind of positive force, a projection of the very things that the Dementor feeds upon — hope, happiness, the desire to survive — but it cannot feel despair, as real humans can, so the Dementors can’t hurt it. But I must warn you, Harry, that the charm might be too advanced for you. Many qualified wizards have difficulty with it."
— Remus Lupin explaining the Patronus Charm[src]

During the 1993-1994 school year, Remus Lupin, then-Professor of Defence Against the Dark Arts offered to teach Harry Potter how to perform the Patronus Charm, as a way to defend himself from dementors that were guarding the school in Anti-Dementor lessons.[1]

These lessons took place in the History of Magic Classroom using a Boggart that Lupin had managed to locate hiding inside Filch's filing cabinet, which he then placed inside of an old packing case. When the lessons started and the packing case was opened in front of Harry, the Boggart would take the form of his worst fear, a Dementor, on which Harry would then attempt to perform the Patronus Charm. Although the Dementor was fake, it still produced similar effects on Harry, and Lupin would give him some chocolate after each lesson to soothe the effects. Harry took several of these lessons with Lupin before he eventually succeeded in creating a Patronus.[1]


Background information


In the summer of 1993, Sirius Black, the most infamous prisoner in Azkaban, escaped from the prison. When informed of this situation, Minister for Magic Cornelius Fudge took many proactive measures in order to corral Black once more. Among these were informing the Muggle Prime Minister and deploying the Dementors into the countryside to search for him.[2]

Sirius Black's wanted poster

At the beginning of the school year, fearing that Black might attempt to kill Harry Potter, Fudge dispatched the Dementors to protect Hogwarts School of Witchcraft and Wizardry and search Hogsmeade village.[3] On 1 September, the Hogwarts Express was searched by the Dementors. When a Dementor reached Harry's compartment, Harry was uncharacteristically affected by its presence. He began to have a fit and could hear a woman screaming in his head.[3] Ginny Weasley was also greatly affected, but not to the extent that Harry was, as he passed out from the experience. Professor Lupin drove off the Dementor by using the Patronus Charm. Once the Dementor was gone and Harry and his friends had eaten some chocolate, they all began feeling much better. However, the whole experience unnerved Harry that none of the others had been as greatly effected as he had been.

Word spread quickly about Harry's reaction to the Dementors on the train, causing a great deal of taunting from the Slytherin students over the incident, especially Draco Malfoy and his cronies. Harry did not have another run-in with a Dementor until his first Quidditch match versus the Hufflepuff Quidditch team.[4] The Dementors invaded the match seeking to feast off the high-running emotions. This time instead of just one Dementor, Harry was faced with at least a hundred of them, and was once again greatly affected by their presence and passed out, falling fifty feet from his broom.[4]

The lessons

Harry Potter: "You made that Dementor on the train back off... Can you teach me?"
Remus Lupin: "I don't pretend to be an expert at fighting Dementors, Harry... all right. I'll try and help."
— Harry asking Professor Lupin for help with the Dementors[src]

Remembering that Professor Lupin had somehow driven the Dementor away on the train, after Harry was released from the Hospital Wing, he asked if Professor Lupin would teach him how to fend off the Dementors. Lupin was initially reluctant, but after seeing Harry's determination, he relented. However, Lupin told Harry that their lessons would have to take place after the Christmas holidays as he was feeling under weather.[5]

"The incantation is this — Expecto patronum!"
—Lupin teaching Harry the charm's incantation[src]

Harry's first attempt at fending of the Boggart

They began their first lesson early in January in the History of Magic classroom.[1] Professor Lupin had procured a Boggart from Caretaker Filch's office. When he explained to Harry that the Boggart would take the form of a Dementor and that it would create a more real experience, Harry was apprehensive, but tried to sound reassured.[1] Before he released the Boggart, Lupin taught Harry the incantation, Expecto Patronum, and gave Harry a short lecture on the Patronus Charm and its effects. Then he told Harry to concentrate on one single happy memory, and when Harry informed him that he was ready they tried it once without the Boggart, and Harry was able to conjure a thin wisp of vapour.[1] Next, Lupin unleashed the Boggart.

Harry conjures an incorporeal shield Patronus

Harry tried many times to conjure a Patronus, but he failed and soon collapsed.[1] Lupin fed him some chocolate and asked if Harry still wanted to continue. Harry, of course, was not going to quit, so they tried again after Lupin told Harry to pick a stronger memory. The result was the same, but Harry did not want to stop, even though Lupin was having reservations. Once more they tried, after Harry had picked another memory, and Harry managed to produce a shield.[1] He was putting all of his strength into holding the Dementor-Boggart at bay, when Lupin banished it. Lupin was happy that Harry had managed the spell, but it cost Harry all his strength.[1]

After a few lessons, Harry lamented at his lack of progress.[1] He remarked that he had hoped he would be able to conjure something that would drive the Dementors completely away instead of just temporarily shielding him, as holding on to the shield took so much out of him. Lupin told him that a true Patronus would do just that, but for a thirteen year old wizard, Harry was doing extremely well and should be able to, at the very least, reach the ground should the Dementors made another appearance at a Quidditch match.[1]

First corporeal Patronus

"Something silver-white, something enormous, erupted from the the end of his wand."
—Harry conjures his first corporal Patronus during a Quidditch match[src]

During the next Quidditch match, Harry was again faced with what he thought were Dementors, he reacted instinctively and cast the Patronus Charm just before grabbing the snitch, winning the game for Gryffindor. Afterward, he found out that what he thought were Dementors were actually Malfoy and his cronies trying to scare him, their plan backfiring on them when instead of scaring Harry they themselves are scared by Harry's first corporeal Patronus chasing them down.[6]


"If I'm proud of anything I've done this year, it's how much you've learned.... Tell me about your Patronus."
—Professor Lupin addressing Harry's education[src]

Harry's Patronus fends off hundreds of Dementors

Harry would be called upon to use the Patronus Charm in a life threatening situation soon enough. In June, Harry discovered that his godfather, Sirius Black, had not, in fact, betrayed his parents, but it had been Peter Pettigrew who performed that dastardly task.[7] For a glorious half hour, Harry believed he would finally be rid of the Dursley family. That was snatched away when the full moon rose, and Lupin, who had forgotten to take his Wolfsbane Potion, transformed into a werewolf. Amidst the commotion, Pettigrew managed to transform back into a rat and escape. Sirius was injured trying to protect Harry and his friends from Lupin, so when the Dementors found him by the lake, he was unable to defend himself or to get away.[8] Harry and his friend Hermione Granger tried to defend Sirius from them, but after holding out briefly, Harry's Patronus shield was overcome by the Dementors, one of whom tried to perform the Dementor's Kiss on Harry. The Dementors were driven away by a powerful Patronus, but Harry could not identify his saviour.[8] When Harry and Hermione used the Time-Turner to go back in time, Harry discovered that it was he who had cast the Patronus that saved his, Hermione, and Sirius's lives. He then cast the spell driving nearly one hundred Dementors off.[9]

The following morning when Harry went to speak with Professor Lupin, whom Harry had just discovered had resigned, Lupin asked him about his Patronus. After Harry told him, Lupin confirmed Harry's supposition that his Patronus was "Prongs", and he told Harry how proud he was to have taught Harry so much.[10]

Behind the scenes

Harry's mastery of the Patronus Charm illustrated by Mary GrandPré

  • In the film adaptation of Harry Potter and the Prisoner of Azkaban, Harry only took one of these lessons from Lupin instead of the several mentioned in the book.
  • In the film version, the lesson takes place in the Astronomy Room (the set for which had been previously used for Dumbledore's office in the second film), instead of the History of Magic classroom as in the book version.
  • In the film, Harry was able to produce a non-corporeal Patronus on only his second attempt.
  • In the original U.K. version of the text of Harry Potter and the Prisoner of Azkaban, when Lupin explains his reasoning for not allowing Harry to tackle the boggart, the text reads regarding Harry's response "I did think of Voldemort at first,' said Harry honestly. "But then I I remembered those dementors." In the U.S. edition, this was changed to read "I didn't think of Voldemort," said Harry honestly. "I I remembered those dementors." The first version is technically more true, as the earlier text stated that "His first thought was Lord Voldemort a Voldemort returned to full strength. But before he had even started to plan a possible counterattack on a boggart-Voldemort, a horrible image came floating to the surface of his mind... A rotting, glistening hand..." The second statement, however, is also true in a sense, as while he did briefly think of Voldemort, his actual fear was the dementors (or "fear" itself) and this was the form his boggart ultimately took.[11]
  • The different versions of the Prisoner of Azkaban video game give very different depictions of these lessons, as contrasted with the novel.


Notes and references

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