10 Even More Movie Mistakes Directors Refused To Fix Because The Acting Was Too Good

The world's cutest Aryan, Draco Malfoy is positioned as the main foil of Harry Potter throughout the books and films.

Whoops, sorry, that should be "Pppppppppppp-otter!"

In order to gain access to the Slytherin common room in the second film, Harry and Ron brew some polyjuice potion to disguise themselves as Gregory Goyle and Vincent Crabbe.

The problem with looking and sounding like Malfoy's heavies though is, well, you have to talk to Malfoy.

Upon spotting his henchmen, Draco asks Goyle why he's wearing glasses. Incognito, Harry responds that they are for reading, to which his boss replies "I didn't know you could read."

It's an absolute zinger from Malfoy, one of his best lines in the entire series. And, you guessed it, it was totally improvised.

Actor Tom Felton has admitted that he totally forgot his scripted line and made up this response on the fly. You can even see Felton's face going blank in the scene, as he quickly realises he needs to say something.

Kudos to the child star for not only keeping the scene going, but for also providing such a killer line off the top of his head.

Hopefully Tom's father heard about this.