The most common and most likely answer to this crossword clue is the 12 letter word SCREENWRITER
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More clues leading to the result SCREENWRITER
- Worker in Hollywood to vet, heard to be not so leftwing?
- Script producer has to check court document with Her Majesty
- Sort out legal document over outsiders in error for a director’s colleague?
- One puts words into the mouths of those to be shot
- During filming entire crew’s performance relies initially on him
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SCREENWRITER mean?
SCREENWRITER noun- One who writes for the screen, who writes drama for film or television; especially a professional who knows the conventions appropriate to such work.