Does Harry's cloak make the wearer invisible to all charms and spells?

Question

In "Harry Potter and the Half-Blood Prince" in the end of the "That's for my father" incident with Malfoy on the Hogwarts Express, Luna Lovegood finds Harry Potter under his cloak with the help of Wrackspurts revealing glasses.

But in the books this cloaks make the wearer invisible for any charms and spells. Is this a plot inconsistency or just a screenwriter have written a bit of nonsense?

Answer 1

But in the books this cloaks make the wearer invisible for(from) any charms and spells.

This assumption is incorrect on your part. I would like to draw your attention to the scene right before Dumbledore is killed by Snape. Harry and Dumbledore come back to Hogwarts after destroying a Horcrux.

'Go and wake Severus,' said Dumbledore faintly but clearly. Tell him what has happened and bring him to me. Do noth- ing else, speak to nobody else and do not remove your Cloak. I shall wait here.'

So at this point we have established that Harry is wearing the cloak of invisibility. Now, cut to the scene where Dumbledore is disarmed.

Then, by the light of the Mark, he saw Dumbledore's wand flying in an arc over the edge of the ramparts and under-stood ... Dumbledore had wordlessly immobilised Harry, and the second he had taken to perform the spell had cost him the chance of defending himself.

This proves that the wearer of the invisibility clock is not immune to spells and charms but merely invisible to the naked eye.

Answer 2

The way I understood the scene, Luna was able to see the wrackspurts around him. I see it being similar to how flies might be circling an invisible trash can. Luna's beliefs in such things may be considered insane by most of the wizarding community, but I guess that's just how they decided to do the scene. Therefore, I would say it's a plot inconsistency/hole.

In response to those who feel that Dumbledore's ability to immobilize Harry at the end of book 6 is evidence that the cloak does not ward against spells or magical abilities, we must remember that this is Dumbledore we're talking about. Dumbledore is considered the most powerful wizard in living memory, possibly of all time.

• In book 2, it's hinted that he was able to see through Harry's invisibility cloak in the scene with Hagrid being arrested and Dumbledore being removed from the school.
• In book 7, it's stated that invisibility cloaks are not infallible, that the charm or effect wears off over time. Dumbledore rejects the belief that the hallows were created by 'death' instead believing they were just created by 3 very powerful wizards.

If that is the case, then it can simply be explained by Dumbledore's petrification spell being strong enough to pierce any protections that the invisibility cloak might have.

However, in book 7 it's also shown that Harry's invisibility cloak was resistant to spells:

• The Thief's Downfall, supposed to remove any magical effects, did not affect the cloak when they broke into Gringott's.
• When Harry, Ron, and Hermione apparate into Hogsmeade, a Death Eater hears the noise and attempts to summon the cloak off of them, which has no effect, not even a minimal one.

Then again, In the beginning of book 6, it's shown that Draco Malfoy used Petrificus Totalus on Harry while he is invisible due to the invisibility cloak, on the train ride to Hogwarts. While Malfoy's abilities are noted to have increased significantly between books 5 and 6, it is all but guaranteed that he was still nowhere near Dumbledore's capabilities. With the events in book 7 displaying the resistance properties of the invisibility cloak more prominently than any of the previous books, I think this is just a plot hole, this time by J K Rowling. As above, a death eater's spell had no effect on the cloak and the Thief's Downfall securing Gringott's from magical intrusion is likely to be a far more powerful effect than Malfoy's Petrificus Totalus.

Answer 3

If I remember correctly, in the books, it's Tonks who got Harry off the train. She did so with the use of a spell, the same way Malfoy petrified him. While it is completely possible to still affect the person wearing the cloak with spells, it's also feasible she could have used the glasses to "see" Harry.