Essentially, director's movie featuring Heather is a wrap (9)
I believe the answer is:
clingfilm
'a wrap' is the definition.
'essentially director's movie featuring heather' is the wordplay.
I cannot really see how this works, but
'movie' could be 'film' (synonyms) and 'film' is found in the answer.
'heather' could be 'ling' (synonyms) and 'ling' is found in the answer.
A single letter 'c' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'is' acts as a link.
Can you help me to learn more?
(Other definitions for clingfilm that I've seen before include "Thin plastic wrap for food" , "Thin transparent plastic wrap" , "Thin polythene for wrapping food etc" , "Transparent wrapping material for food" , "Sticky wrapper" .)