We all know that the beaded bag is enchanted to carry more objects than it can carry under normal laws of physics, the thing is, this bag is the perfect source of a distraction when its dropped....

During Bill and Fleur's wedding, Hermione meets Krum again and at that moment drops her bag which makes "a CRASH that was quite disproportionate to its size".

During some tight spot in the movie they can make Hermione drop her bag making a extremely loud CRASH which makes death eaters or similar look around to see what on earth just happened and that proves to be the distraction Harry needs to escape or do whatever he wanted to do

No... I don't think that would be a good scene to put in. First of all, Hermione wouldn't be focusing on trying to distract the Death Eaters with a loud noise. She would probably be casting spells at them. Besides, I don't think most of the death Eaters would be silly enough to look for the source of the noise.

and then like ron in first movie yelling oi pea brain at the troll the attention would then be hermione which puts her in danger unless she trows the bag and then she would have to leave it then they would be pretty... wel stuffed

I think they may look more to the decoy detinator to be something other then her beaded bag. It is a good thought though. I think her bag is going to be used in different ways.

And what happens if the Death Eaters catch the bag?

Now they have everything they have in that bag.

From the tent and cooking stuff to polyjuice potion.

They can instead use dungbombs or destroy some roof or set something on fire.

But basically I don't want the moviemakers to change such major things from the book.

I agree with mihirviveka, the bag is too valuable to simply drop and leave it. There is the tent, the supplies, the Polyjuice Potion. And Harry could just as easily use Stupefy or Expelliarmus, as we all know he loves the latter

It is a good idea though, or to throw it at them, with all of the metal and its weight...I wonder how Hermione can manage to lift it?

I would assume that the enchamntment makes it seem as if the bag isnt so full of stuff. So the bag probably only weighs like 2-3 pounds because the enchantment would obviously not effect the weight

That is true, and the enchantment is an Undetectable Extension Charm, so weightlessness would make it more undetectable as well.

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