Fussy girl with retired agent taking in film (10)
I believe the answer is:
pernickety
'fussy' is the definition.
(synonyms)
'girl with retired agent taking in film' is the wordplay.
I cannot quite see how this works, but
'retired' could be 'r' (abbreviation) and 'r' is found in the answer.
'girl' could be 'pen' and 'pen' is found within the leftover letters.
'film' could be 'et' (E.T. the Extra-Terrestrial) and 'et' is located in the answer.
The remaining letters 'icky' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
(Other definitions for pernickety that I've seen before include "Particular" , "Over-particular" , "Paying too much attention to trivial details" , "Fussy" , "Over-precise" .)