The Fidelius charm - how it works and where it can be used

[RavenRepented]

I'd like to discuss how Dobby brought Harry and co. back to Bill and Fleur's. Was it just house elf magic that allowed him to appear there? If I remember correctly, Lupin was the Secret Keeper for the house, and while he definitely told Ron about where they were (as he chilled there for a bit), how did Harry and Hermione arrive there if Lupin never told them?

[Elysia]

Here's one to REALLY mess with your minds! What happens when someone makes someone else a Secret Keeper, but the secret isn't actually a secret because someone else already knows about it?

Example: I decide to tell my sister a secret about where I hid something, but my mom already found it in my sock drawer the day before, so even though I think it's a secret, it's really NOT a secret?

Will the magic involved in making a Secret Keeper backfire and notify the wizard casting the spell that the secret is already out, or will it just carry on as if the secret was really still a secret?

Hmmmm.....

[Urania]

I may be way off track here, but as I understood it they didn't put the Fidelius Charm on their house (or the Burrow, og Muriels (sp.?) place) untill after Harry and the others had appered.
They were only really in danger once it was official that a Weasly was fighting alongside with Harry...
And wasn't Bill secret keeper??

Originally Posted by Elysia

Here's one to REALLY mess with your minds! What happens when someone makes someone else a Secret Keeper, but the secret isn't actually a secret because someone else already knows about it?

Example: I decide to tell my sister a secret about where I hid something, but my mom already found it in my sock drawer the day before, so even though I think it's a secret, it's really NOT a secret?

Will the magic involved in making a Secret Keeper backfire and notify the wizard casting the spell that the secret is already out, or will it just carry on as if the secret was really still a secret?

Hmmmm.....

I believe the knowledge "disappears", I mean... the Black family must have had for example Bellatrix and Narcissa in the house on visit, but after The Order decides to use it as headquarters.
Even though they must have been there before, they were suddently unable to find it. I would be VERY much surprised if Bella wasn't one of the DE's standing guard outside when the trio is there, since she knew where the house was supposed to be.

[TeraBlight]

Fidelius Charm in relation to the aftermath of Voldemort's attack on Harry's parents also discussed here.

[muggleborn1]

Originally Posted by nano

And I still dont really understand how Hagrid could pick up Harry from Godrics Hollow if the secret hadnt been lifted. If it had - no problem Bathilda saw what had happened and told DD but if it hadnt - how did they find the house? It was the house the secret was on, not the potters, other wise I would have thought the secret was no longer a secret after their death, but James used the invisibility cloak to roam around, meaning the place had the secret on it not the people.

In regards to this portion of your question: The fact that there was a FC in place doesn't mean that ONLY wormtail knew the location of the Potters. It means that ONLY people wormtail TOLD DIRECTLY know the location of the potters. And even those who KNOW the location are unable to reveal the location....

Notice in the letter from Lily to Sirius that Harry finds, she asks Sirius if the gets a chance to come and visit. And Bathilda was coming over daily to visit. Clearly there were people who knew the location of the potters, probably a good portion of the Order knew their location and could check on them as needed.

I assume Hagrid was among those who knew the location and when word of the attack got out, he was sent to pick up Harry.

As to when the FC was broken and the house became visible to everyone, I don't know the answer, unless as has been suggested, Lily was the one to cast the charm (seeing as we know she was "good at charms"), and the charm died with the caster. That seems to be as good a theory as any I've heard.

[Hermie]

I'm also puzzled after examining Jo's quote again:

Just in case you have forgotten exactly how the Fidelius Charm works, it is

"an immensely complex spell involving the magical concealment of a secret inside a single, living soul. The information is hidden inside the chosen person, or Secret-Keeper, and is henceforth impossible to find -- unless, of course, the Secret-Keeper chooses to divulge it" (Harry Potter and the Prisoner of Azkaban)
In other words, a secret (eg, the location of a family in hiding, like the Potters) is enchanted so that it is protected by a single Keeper (in our example, Peter Pettigrew, a.k.a. Wormtail). Thenceforth nobody else – not even the subjects of the secret themselves – can divulge the secret. Even if one of the Potters had been captured, force fed Veritaserum or placed under the Imperius Curse, they would not have been able to give away the whereabouts of the other two. The only people who ever knew their precise location were those whom Wormtail had told directly, but none of them would have been able to pass on the information.
nano

What I don't understand is how Bathilda came to visit the Potters while they were in hiding if Wormtail did not tell her the secret! We know from Lily's letter to Sirius (DH p.180) that both Wormtail and Bathilda came to visit the Potters while they were under the Fidelius Charm since James did not have his cloak at that point and had to remain in hiding--Dumbledore had taken the cloak a few days before their deaths (DH p.714). If she knew Peter Pettigrew was the secret-keeper then Sirius would not have been tried for their murders. According to Jo, Wormtail must have told her since even Lily and James could not have told the secret to her either. Wormtail was the single living soul in which the secret was kept. Was Bathilda that far gone at that point?

As to how the Fidelius Charm broke on the Potter's home (it must have since Peter Pettigrew was not dead therefore still the sole secret-keeper and only he could have told Hagrid if it was still in force) I agree that it probably was a specifically worded secret about the house so that if two of the family died the secret was no longer true. Something like "The home of the Potter family is at..." or "The home of Lily and James Potter is number...." Since the Lily and James were dead, the house in Godric's Hollow was no longer their home, and therefore no longer hidden so that they were able to safely retrieve Harry.

Dobby being able to apparate at Shell Cottage (also under the Fidelius Charm), they only apparated outside the cottage, although for some reason they could see it. I'm not sure that the Fidelius Charm can be broken by house-elves so that they can transport people who don't know the secret into them like ChibiHermione suggests, though of course it's highly likely that Death Eaters would underestimate their power, like LV underestimated Kreacher and left him to supposedly die in the Inferi cave. They most certainly can break the no-apparate spell as demonstrated by Dobby going in and out of Hogwarts and the Malfoy residence with passengers (Snape and Yaxley must apparate outside the gates).

[TeraBlight]

Originally Posted by Hermie

If she knew Peter Pettigrew was the secret-keeper then Sirius would not have been tried for their murders. According to Jo, Wormtail must have told her since even Lily and James could not have told the secret to her either. Wormtail was the single living soul in which the secret was kept. Was Bathilda that far gone at that point?

This question has been batted around a lot prior to "Hallows", and AFAI am aware there were really only two possibilities: Either Sirius really was the only person who knew the Potter's location, in which case Wormtail simply didn't reveal the secret to anyone else before betraying it to Voldemort, or... Wormtail wrote the secret down, gave the note to someone else (say, to James, who passed it on to, say, Dumbledore, without telling him who it was written by), and then Dumbledore showed the note to whoever else was supposed to know the secret. We know that this works in principle because Dumbledore, Alastor and Harry do the same thing for the location of Headquarters in "Phoenix".
Since the "no visitors" theory is ruled out by Lily's letter, the "note" theory would seem to be the only remaining option.

Another detail from the explanation on JKR's site:

[...] a secret (eg, the location of a family in hiding, like the Potters) [...] Even if one of the Potters had been captured, force fed Veritaserum or placed under the Imperius Curse, they would not have been able to give away the whereabouts of the other two.[...]

If we take this literally, it clearly implies that the whole family, not just James and LIly, were covered by the Charm. So Harry's explanation in "Hallows" as to why the Charm broke ("must have died with James and Lily") only makes sense if one of them cast it, and not because the secret was no longer existent.

[Hermie]

Gah, you're right. I thought James, Sirius, and Dumbledore would not have been so careless by passing around a note with such vital information, but Wormtail certainly would have been and would have wanted to have kept his identity hidden from as many people as possible. James probably would have gone along with it to protect Wormtail. Dumbledore only used the note the one time for Grimmauld Place to avoid direct contact with Harry.

I'm not so sure the Fidelius Charm dies with the caster. I'm almost positive that Dumbledore placed the Fidelius Charm on Grimmauld Place, and it stayed intact after his death (the death eaters knew the location but couldn't see the place). It must be one of the spells that stay in place after death, since there are tons of ancient magical items and places like Hogwarts and Griffindor's sword. Come to think of it I only remember curses being lifted after the death of the caster. Perhaps a Fidelius Charm is lifted after those inside the actual location are attacked by someone on the secret--meaning the charm is useless.

[Urania]

I really doubt that the charm was worded like "The hiding place of Lily and James Potter" since the soul point of hiding at all was Harry.
Hagrid says in PS that he took Harry out before "the muggles started swarming" (or something like that) - which must have ment that the curse broke before he removed Harry. I really believe in Lily (or James, but I think Lily's more likely) cast the spell, otherwise it doesn't make sense for the charm to break while Harry (who it is supposed to protect) is still in the house.

[yrome]

Thank you nano! This has been bothering me for a bit, and I was debating this point today with someone. She seemed to think that people (Hagrid, DD, etc.) who already knew where the Potters lived (and therefore where they were hiding) wouldn't need to be told where it was since it was something they already knew. Using this logic, then, Hagrid would not have to hear it from Peter to go and pick up Harry because he already knew where they lived. Only someone who didn't know where it was, like LV, would need to be told where the Potters were, and the only one who could tell was Peter. It sort of explains things, but I don't like it. I pictured the FC as being encompassing, as in the location of Harry, Lily, and James was the secret, and only those who were told by Peter where they were could see them. I thought people would still be able to go the house, but they wouldn't be able to see them unless they were told by Peter that they were there. I submitted the question of how Hagrid was able to get baby Harry for the live chat thing, hope it gets answered b/c it is driving me bonkers.

[nano]

Originally Posted by yrome

Thank you nano! This has been bothering me for a bit, and I was debating this point today with someone. She seemed to think that people (Hagrid, DD, etc.) who already knew where the Potters lived (and therefore where they were hiding) wouldn't need to be told where it was since it was something they already knew. Using this logic, then, Hagrid would not have to hear it from Peter to go and pick up Harry because he already knew where they lived. Only someone who didn't know where it was, like LV, would need to be told where the Potters were, and the only one who could tell was Peter. It sort of explains things, but I don't like it. I pictured the FC as being encompassing, as in the location of Harry, Lily, and James was the secret, and only those who were told by Peter where they were could see them. I thought people would still be able to go the house, but they wouldn't be able to see them unless they were told by Peter that they were there. I submitted the question of how Hagrid was able to get baby Harry for the live chat thing, hope it gets answered b/c it is driving me bonkers.

This has also had my mind boggled since we found out about the FC - but it cant be that those who already knew where the potters lived didnt need to be told the secret - as someone has already written - Bella & Narcissa both must have known Grimmauld Place - they certainly knew Kreacher - but they still couldnt get to the place.

I was also under the impression in DH that the place could not be seen by muggles - so why did Hagrid turn up before 'the muggles started swarming the place" ? Or was that a different protection put on after the FC had been broken, such as Grimmauld Place had always been unplottable und non existant to muggles?

If the secret dies with the caster as some have said on here - why then is Grimmauld Place still under the FC?

If all told became secret keepers then why were only protections put up in case Snape wanted to blab - what about Kreacher? He never accepted Harry as master till DH, so he could have blabbed also, as he was in on the secret - or did he fall into the house elves different magic category?

Another thing that was brought up was how Dobby apparated to Shells Cottage - Bill was the secret keeper for that place. To me thats another hole in the FC - or security breach if it is different for House elves.

I hope someday Jo clarifies exactly how the FC works - this is driving me mad ( I know I should get a life, but hey no more HP books to look forward to - whats the point, I'm in a Post Potter Depression )

nano

[TeraBlight]

Originally Posted by nano

If all told became secret keepers then why were only protections put up in case Snape wanted to blab - what about Kreacher? He never accepted Harry as master till DH, so he could have blabbed also, as he was in on the secret - or did he fall into the house elves different magic category?

Ah, now that's an interesting aspect. Did Dumbledore have to tell Kreacher the Secret? More generally, what happens to a person who's AT the location that is being protected by the Charm at the time at which it is cast?
The most reasonable explanation, to me, is that those people immediately gain the same status as people who are told by the Secret Keeper. After all, we know because of the Yaxley-Apparation-incident in "Hallows" that communicating the secret, verbally or in writing, is not the only way to pass it on, but that a Secret Keeper can also simply bring a person to the protected place.

So, yes, I'd think that upon Dumbledore's death Kreacher indeed became a Secret Keeper. However, IIRC Harry restricted him to Hogwarts to prevent him from having any more contact with Death Eaters, and by the time they took over Hogwarts Kreacher was already reformed, so we might not have to bring up the "House Elves can break all the usual rules" argument for this one...

[tehnotlocity]

And I still dont really understand how Hagrid could pick up Harry from Godrics Hollow if the secret hadnt been lifted. If it had - no problem Bathilda saw what had happened and told DD but if it hadnt - how did they find the house?

Well we know that Bathilda had known the wherabouts of the Potter's, because Lily's letter to Sirius mentioned her coming to visit. I think we can assume, then, that others who were close to the Potters - Sirius and Dumbledore certainly, and possibly Hagrid - knew the secret.

Here is my question - I think it is reasonable, as above stated, for Hagrid to have known the secret, but how could Hermione see the house? And all of those who had written on the sign outside?

[TeraBlight]

Originally Posted by tehnotlocity

Here is my question - I think it is reasonable, as above stated, for Hagrid to have known the secret, but how could Hermione see the house? And all of those who had written on the sign outside?

We know that the Charm breaks when Voldemort inadvertently blows up the house at the latest, because Hagrid tells Dumbledore that he "got him out all right before the Muggles started swarmin' around." The question is why the Charm broke.

[yrome]

Originally Posted by tehnotlocity

Well we know that Bathilda had known the wherabouts of the Potter's, because Lily's letter to Sirius mentioned her coming to visit. I think we can assume, then, that others who were close to the Potters - Sirius and Dumbledore certainly, and possibly Hagrid - knew the secret.

But HOW did they know? They could only know if Peter told them, and if he did, then they would have known he was the secret-keeper and not Sirius. It just doesn't add up.

As for Dobby apparating to Shells Cottage - maybe he apparated to the right place - outside the enchantment, and when Bill took a look outside, he saw them and told them the secret, so they saw it. Harry popped up in the right place as well, but it seemed a bit away from the house. I'm not sure, though, I have to go back and read that section b/c I am seriously confused.

[nano]

Originally Posted by TeraBlight

Ah, now that's an interesting aspect. Did Dumbledore have to tell Kreacher the Secret? More generally, what happens to a person who's AT the location that is being protected by the Charm at the time at which it is cast?
The most reasonable explanation, to me, is that those people immediately gain the same status as people who are told by the Secret Keeper. After all, we know because of the Yaxley-Apparation-incident in "Hallows" that communicating the secret, verbally or in writing, is not the only way to pass it on, but that a Secret Keeper can also simply bring a person to the protected place. ...

That fact also puzzles me - about Yaxley knowing, because he apparated there with him. I was under the impression you had to be told either verbally or in written form by the secret keeper. In OotP there was so much wahoo over getting Harry safely to Grimmauld Place - I know DD didnt want to be around Harry because of his supposed connection to LV, but surely for Harrys sake he could have done side along apparition to the Doorstep (perhaps with Harry blindfolded) to ensure Harrys safety.

Originally Posted by TeraBlight

We know that the Charm breaks when Voldemort inadvertently blows up the house at the latest, because Hagrid tells Dumbledore that he "got him out all right before the Muggles started swarmin' around." The question is why the Charm broke.

Originally Posted by tehnotlocity

Well we know that Bathilda had known the wherabouts of the Potter's, because Lily's letter to Sirius mentioned her coming to visit. I think we can assume, then, that others who were close to the Potters - Sirius and Dumbledore certainly, and possibly Hagrid - knew the secret.

Here is my question - I think it is reasonable, as above stated, for Hagrid to have known the secret, but how could Hermione see the house? And all of those who had written on the sign outside?

If the charm broke, then that would reason the statement about the 'muggles swarming around'. I think the protection that is now on the house is not the FC, but like the other protections on Grimmauld place, that only wizards can actually see the house. It must be totaly 'not there' to the muggles, not just a ruined schack like Hogwarts would look like to a muggle. If not the council would have cleared the place up years ago. It is now a kind of monument to the wizarding world.

Originally Posted by yrome

But HOW did they know? They could only know if Peter told them, and if he did, then they would have known he was the secret-keeper and not Sirius. It just doesn't add up. ...

That has puzzeld me all along - How did they know and not know about the swap of the secret keepers. Unless it was yet again told by a piece of paper.

nano

[muggleborn1]

Originally Posted by nano

That has puzzeld me all along - How did they know and not know about the swap of the secret keepers. Unless it was yet again told by a piece of paper.

I think that's the most likely explanation. Because of the delicate nature of the secret, I would guess that regardless of WHO the secret keeper was, the location would have been passed by note. If done verbally, even under cover of invisibility cloak, the listener would have been able to discern who the secret keeper was.... and the more people who know the secret keeper, the more at risk said secret keeper is of being captured...

IF passed by note, then the identity of the secret keeper remains secret as well, meaning LV has MANY, MANY candidates to choose from when trying to learn the secret...

[padfootandme]

Pieces of paper would be the smartest way of telling the secret, but there is always that small chance that the paper could be stolen, summoned, misplaced, or shown to the wrong person.

[TeraBlight]

Originally Posted by padfootandme

Pieces of paper would be the smartest way of telling the secret, but there is always that small chance that the paper could be stolen, summoned, misplaced, or shown to the wrong person.

That's why I advocate the idea that the note was kept by Dumbledore, in his office at Hogwarts. I don't see anyone stealing it from there, if he's serious about keeping it hidden and safe.

[Lady_yui]

Originally Posted by Aliena

I think the answer on JKR's website is intentionally incomplete. By saying "the status of their secret will remain as it was at the moment of their death. Everybody in whom they confided will continue to know the hidden information, but nobody else", I think she means that, for example, No. 12 Grimmauld Place would not become visible to everyone just because Dumbledore died. She did not actually say that no one else could reveal the secret after the Secret-Keeper's death, her example involved a Secret-Keeper who was still alive.



I think it was "the location of James and Lily Potter" that was the secret; not the house itself for all eternity, and not James' and Lily' existence (in which case the invisibility cloak would not be needed) - just the fact that they lived in that particular house. Once they no longer lived, the secret was lifted, and the wizarding world could see the house. (I'm assuming there were general anti-Muggle charms on the house, or the ruins would have been cleared long ago!) Hagrid finding Harry was never problematic for me - it was Sirius finding him that was puzzling, because Sirius did not know that Wormtail was the Secret-Keeper, and so could not have been told the secret by him.

I think the enchantment was not lifted when someone dies.Wasn`T it mentioned in the DH?I think it was hermione and harry talking when they were at Godric`S hallow about not being able to build a new house because of the FC. This question really kept bugging me even before the DH was released because how did Harry,Hermione and Ron knew the place?Maybe they only knew the village but the saw the ruins of the house when they got there ryt?I kept re-reading J.K`s answer to this but it doesn`T fits.