To adapt is to write. Even if the author does not start from the blank page, he is none the less confronted with multiple constraints and technical contingencies.
And it will also have to position itself, in its intentions, in relation to the existing work that provides it de facto with a framework, a presupposition, codes and foundations.
The author, as a creative actor, will have to evaluate as much as possible his freedom to transgress, his degree of loyalty and the desires of his various sponsors and partners.
Beyond this knowledge and the necessary professionalism to give to this approach, one must succeed in establishing one’s own rules of authorship and in appreciating those of others in the particular case that each adaptation will be.