To change the future to better one

Harry and Ron transformed

The Christmas Feast. The hall glimmers grandly as snowflakes tumble from the ceiling. Harry and Ron sit with Hermione.

Hermione: Everything's set. We need a bit of who you're changing into.

Harry: Crabbe and Goyle

Hermione: And we also need to make sure that the real Crabbe and Goyle can't burst in on us while we're interrogating Malfoy

Ron: How?

Hermione Holds up a pair of cupcakes

Hermione: I've got it all worked out. I've filled these with a simple sleeping draught. Simple, but powerful.

All looked at her jaw dropped

Lily whispered, " That's a third-year potion!"

Sahithi sighs dramatically saying " Mione my lovely flower let's get away and get married"

All laughed at that as Harry just tickled Sahithi which made her squeal and laugh

All the F.G smiles at that

Ron glances at malfoy, Crabbe, and Goyle who are presently eating everything in front of them

Hermione:  now, once they're asleep hide them in a broom cupboard and pull out a few of their hairs

Ron: and whose hair are you ripping out?

Hermione: I've already got mine

She removes a small vial, inside is a tiny hair

Hermione: Millicent Bulstrode, She's in slytheirn. I got this off her robes

Ron and Harry snort as Hermione glares at them

Millicent just giggles with Hope saying

" Oh mione you didn't"

Hermione just groans in her hands as everyone looks confused

Hermione: All right them...I'm going to check on the polyjuice potion

Hermione exits, ron looks at Harry

The next thing we know Harry and Ron lurking behind a suit of armor, watching Crabbe and Goyle exit the great hall,  Goyle spies the cakes instantly and grabs them he reluctantly saunders one to goyle they stuff them into their mouths they pause look at each other and fall flat onto their backs. Harry and ron dash our drag Crabbe and Goyle across the floor and into a cupboard

Jasmine looked at them with a deadpan face saying " You could use a Levitation charm you know?"

Both Harry and ron groan in realising as 

Harry said, " Why didn't we think of that?"

All laugh at that

Hermione wearing a Slytherin robe, Hovers over a smoking cauldron. Harry and Ron enter

Hermione: Did you get it?

Harry and Ron Hold up their hands, In each a tuft of hair, Hermione points to a pair of Slytheirn robes

Hermione: I sneaked those out of the laundry

Harry and Ron nod and glance at the cauldron, the potion resembles a thick dark bubbling mud

Hermione: I'm sure I've done everything right. It looks like the book said it should. Once we've drunk it, we'll have exactly one hour before we change back into ourselves