Movie in the mist (4)
I believe the answer is:
film
This clue is a double definition.
'movie' is the first definition.
(I know that movie can be written as film)
'the mist' is the second definition.
(thesaurus)
'in' acts as a link.
(Other definitions for film that I've seen before include "Cinema celebrity" , "Thin coating for movie." , "Thin coating or covering layer" , "Moving picture" , "Flick" .)