Girl in film is seductive (4)
I believe the answer is:
miss
'girl' is the definition.
('miss' can be a synonym of 'girl')
'in film is seductive' is the wordplay.
'in' indicates a hidden word.
'MISS' can be found hidden inside 'film is seductive'.
(Other definitions for miss that I've seen before include "maiden" , "Girl or unmarried woman" , "Agatha Christie's detective" , "Fail to perceive" , "Young girl" .)