You don’t have the right to alter a film and resell it.
What about copyright law do you not get?
You can’t do that, its the law, and no amount of cognitive dissonance on your part will change that, ever.
Next time you rent a film, read all the small print when they roll the credits, you don’t have the right to do that. Nor do you have the right to publish someone’s book with your own foreword.