It is established in Deathly Hallows that Polyjuice Potion is meant for human transformations only:

‘Wha’ was tha’ about?’ roared Hagrid.

‘I’m sorry, Harry, but I had to check,’ said Lupin tersely. ‘We’ve been betrayed. Voldemort knew that you were being moved tonight and the only people who could have told him were directly involved in the plan. You might have been an impostor.’

‘So why aren’ you checkin’ me?’ panted Hagrid, still struggling to fit through the door.

‘You’re half-giant,’ said Lupin, looking up at Hagrid. ‘The Polyjuice Potion is designed for human use only.’

Deathly Hallows - page 63 - Bloomsbury - chapter 5, The Fallen Warrior

And it's established Fleur Delacour is part Veela in Goblet of Fire:

[Ollivander] twirled the wand between his long fingers like a baton and it emitted a number of pink and gold sparks. Then he held it close to his eyes and examined it carefully.

‘Yes,’ he said quietly, ‘nine and a half inches ... inflexible ... rosewood ... and containing ... dear me …’

‘An ’air from ze ’ead of a Veela,’ said Fleur. ‘One of my grandmuzzer’s.’

So Fleur was part Veela, thought Harry [.]

Goblet of Fire - page 270 - Bloomsbury - chapter 18, The Weighing of the Wands

Why was Fleur able to take Polyjuice Potion and transform into Harry while Hagrid was not? Neither Fleur nor Hagrid are fully human.

I'm not interested in an answer that says it was possible because Fleur had more human blood than Hagrid. It's clear from canon that "human use only" means human use only. Can this discrepancy be explained within the spirit of canon? I don't know of a canon explanation for this question, or that J.K. Rowling addresses it in any of her interviews, but if you can find a quote or passage from the books that answers this, I would love it if you left an answer. Please no HP Wiki/Wikia answers.

I checked for this question under "Fleur" and didn't find it. I hope it's not a dupe.

  • 17
    I would guess it's not so much an arbitrary "more human blood than Hagrid" as it is "more human blood than Veela blood". Hagrid's exactly half/half. (But, just a guess - hence why it's a comment ;) )
    – Izkata
    Commented Jun 27, 2012 at 0:16
  • 4
    Good one. I don't think there can be an in-universe answer to this. Veela may be able to look like humans (and beautiful ones at that) but from how they changed appearance at the Quidditch World Cup, they're definitely very different. At least as different as giants or goblins are. Neither are classified as "beasts" according to "Fantastic Beasts & Where To Find Them", but neither are they human. I think this is one of those mistakes JKR says she's made. Commented Jun 27, 2012 at 0:47
  • 1
    @Izkata - Well, okay, semantics, and I see where you're coming from. My thought, though, is that no matter the percentage, only 100% humans should take Polyjuice. 50% or 75% human isn't enough, if I'm interpreting correctly. This is a tough one! Thanks for commenting :) Commented Jun 27, 2012 at 1:52
  • 2
    @DavidStratton -- Do you have a link to JKR's quote saying this? According to the guidelines in Fantastic Beasts and Where to Find Them I think Veelas would be considered beings in Potterverse while giants would be considered beasts, the difference being that a “being” is any creature that has sufficient intelligence to understand the laws of the magical community and to bear part of the responsibility in shaping those laws. (Scholastic - page xxi) Technically I think this would include goblins as well. Commented Jun 27, 2012 at 2:03
  • 2
    I think I mis-phrased it. Within the last three weeks, I ran across a quote from JKR stating that she's made continuity mistakes (But I can't find the interview now). I think I phrased it to sound like "JKR has said that this is one of her continuity mistakes", when I meant "JKR has said that she's made continuity mistakes, and that I think this is one of them." I also think giants barely squeak into the "beings" category - they have culture, customs, language, and Hagrid went, assuming giants had sufficient smarts to choose sides. And they're not listed in Fantastic beasts. Commented Jun 27, 2012 at 3:28

6 Answers 6


First of all, I think you are slightly confused about directions:

  • Fleur able to take Polyjuice Potion and transform into Harry as you said

  • Whereas, Lupin testing Harry and NOT testing Hagrid meant that he was not worried that Hagrid was a fake Polyjuiced DE impostor.

In other words, what Lupin said was that it is not possible was for a human to transform into a half-giant (or non-human) [remember what happened to Hermione when she Polyjuiced herself into a cat in CS?] - but that didn't imply anything about a cross-breed transforming into human as a target. Thus, Fleur's transform into Harry doesn't necessarily make for a contradiction.

The limitation might only be on the target as opposed to the drinker of the potion.

Leaving aside that obvious explanation, there are 4 options possible based on interpreting canon even assuming that someone could Polyjuice into Fleur (but not Hagrid):

  1. Polyjuice is (unlike Transfiguration) somewhat mass- or volume- dependent. While having different sized humans transform into Harry may be plausible, having a 1000 lb Hagrid who was twice human height is stretchin the laws of science magic - ditto transforming a human into Hagrid.

  2. This is most likely due to Hagrid being part-giant than the proportions. Giants in general seem immune to magic (see the scenes in HBP for example); and therefore it's quite possible that Polyjuice simply doesn't work well on them, same as any other magic.

    One of the reasons stated in canon for Hagrid's magic resistance is general thick-skinness and toughness of giants physically. It's possible that this purely biological physical distinction is problematic for Polyjuice transformation.

    Heck, Hagrid's hair may simply refuse to be dissolved in the potion, being too tough.

  3. Another possibility is that Giants - while technically the same species due to there being possible cross-offspring - are too genetically different from humans compared to Veela. Remember what happened to Hermione when she Polyjuiced herself into a cat in CS - that was likely due to genetic conflicts.

  • 15
    @Slytherincess - that's why I started out explaining why the whole premise is different - Lupin's concern (or rather lack of it) was about a HUMAN taking PJ potion to turn into Hagrid; NOT about Hagrid drinking PJ potion. Which is directly corroborated by Hermione's CS experience. E.g. the rule is NOT about non-humans taking the potion; but about humans using the potion to turn into non-humans Commented Jun 27, 2012 at 2:29
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    Also, sorry but you're reading Lupin 100% wrong. See your quote: "Lupin To Harry: You might have been an impostor.’ - Hagrid: ‘So why aren’ you checkin’ me?’". Hagrid is upset that Lupin didn't verify that HE, Hagrid, was not an impostor - e.g. a DE who looked like Hagrid. THAT was what Lupin was responing to. Commented Jun 27, 2012 at 2:46
  • 8
    @Slytherincess DVK has it right here; The idea is that the potion is designed to transform into a human only, not that only 100% human's can use it. This is supported by canon, we see Hermione fail to turn into a cat, and we see that Lupin doesn't check Hagrid.
    – NominSim
    Commented Jun 27, 2012 at 13:27
  • 11
    @Rob That interpretation of "human use" is not supported by canon. If "only humans should use it", then Lupin would have suspected Hagrid since it could have been a human that used the potion to turn into him. The interpretation that it can only turn the user into a human is supported by canon however. (Hermione with the cat, and Lupin not being suspicious of Hagrid)
    – NominSim
    Commented Jun 27, 2012 at 17:07
  • 12
    @Slytherincess - Lupin sees Hagrid there in front of him, so he isn't talking about whether Hagrid himself could use Polyjuice at all, he is talking about whether someone else could use Polyjuice to turn into Hagrid. It doesn't make sense for Lupin to say "Oh I don't have to worry because you can't use Polyjuice", because Hagrid is standing right there, it was either someone else who had turned into Hagrid, or Hagrid himself. Lupin's comment indicates that the potion is for human use only, meaning it couldn't turn someone into Hagrid.
    – NominSim
    Commented Jun 28, 2012 at 14:49

Assumption: neither Fleur not Hagrid are 100% human.

If Polyjuice Potion can only be used by someone who is 100% human, then

  • Death Eaters could have impersonated either Fleur or Hagrid;
  • Neither Fleur nor Hagrid could have impersonated Harry.

This violates canon, because (1) Fleur could impersonate Harry, and (2) there was no risk that Hagrid could secretly be a Death Eater. Therefor this can't be the case.


If Polyjuice Potion can only be used to turn someone into a human, then

  1. Neither Fleur nor Hagrid could have secretly been a Death Eater.
  2. Either Fleur or Hagrid could have impersonated Harry.

This is rather canon compliant as an explanation and doesn't violate the assumption. In other words, despite the sloppy English, this is the correct interpretation.

  • 1
    Although this does make me wonder if someone could impersonate Remus Lupin; he's not exactly 100% human either as a werewolf. Commented Apr 5, 2013 at 19:31
  • 6
    I dunno: I see werewolves as having caught an incurable disease with moon-induced symptoms. It doesn't change what the victim was born as.
    – Martha
    Commented May 23, 2013 at 21:43

One possibility of course is that Prof Lupin was simply mistaken. He was a bright wizard indeed, but not a potions master, and he may not have known every nuance of the Polyjuice Potion's actions. I have no evidence for this other than the fact that Lupin was human and therefore fallible.

  • 2
    -1 for suggesting that Lupin doesn't know everything. Just kidding ;) But I think that Lupin is very considerate and cautious, so I doubt he wouldn't check Hagrid if he wasn't 100% positive that it was really him.
    – Cephalopod
    Commented Jul 28, 2014 at 8:55

I think the premise of the argument itself is flawed. Hagrid is a half giant. This is established. Hagrid is the direct offspring here. May be Fleur isn't. Imagine two purebloods siring a pureblood who marries a halfblood/muggle to sire a halfblood/squib. In my opinion her grandmother being Veela does not essentially mean she's part Veela.

  • I do not intend to make Harry look stupid here :)
    – Janus
    Commented Jun 27, 2012 at 6:48
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    I gave a canon quote that states Fleur is part Veela. JKR refers to her as "the Veela girl" quite a few times throughout Goblet of Fire. If you read through chapter 16 - The Goblet of Fire - you can confirm this. I don't think "Maybe she's adopted!" or "Maybe she's just not part Veela", when canon clearly indicates she is, is quite what I'm looking for, although of course you're welcome to theorize whatever you'd like. :) Commented Jun 27, 2012 at 11:54
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    Pure/half-bloods, muggles, and squibs are all fully human, the only difference is how much magic they and their ancestors exhibited. Someone with a Veela (i.e. nonhuman) grandmother is only 3/4 human. Period.
    – Kevin
    Commented Jun 29, 2012 at 3:14

Size may also be a factor, Fleur was human sized as well as being 3/4s human. Where as Hagrid was 1/2 human and if you go by the books at least 11ft tall and probably weighed close to a ton

  • Is there any evidence to support this, or are you just speculating? Speculation alone doesn't make for a very good answer. Commented Feb 27 at 20:06

The simple answer is that Fleur is 3/4 human while Hagrid is only 1/2. Plus Hagrid is alot bigger then Harry and Fleur so the magic probably isn't designed to turn somthing that big into somthing so much smaller, hence Hermione and the cat hair. The last reason could be simply that the Wizarding world is not fact and is created by a human being who will make mistakes from time to time meaning Harry Potter shouldn't be read like a non-fiction text book

  • Please don’t insult question askers and your final point isn’t also much of an answer. Because it’s fiction, the writer wrote so or the writer made a mistake are generally considered non answers.
    – TheLethalCarrot
    Commented Jun 10, 2020 at 7:15
  • I wasn't trying to insult anyone, if that was how I came across then I apologise. Also I am new to this website and it feels a bit like you are being a bit judgmental and seem to critisize everything I write. I have only written twice and both times you have edited and critisized what I have written. Can you please stop that? Once again I apologise if i sounded rude before
    – Lucy
    Commented Jun 11, 2020 at 5:35
  • Editing is just part of how content is curated on this site, here all I did was remove what is essentially an insult from the start of it. You might want to take the tour if you haven’t already because it gives some insight into how this site works as it is different to a typical discussion forum. And for what it’s worth I didn’t criticise or “judge” your question but actually defended it to another user.
    – TheLethalCarrot
    Commented Jun 11, 2020 at 6:49

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