Scrooge in film is erratic (5)
I believe the answer is:
miser
'scrooge' is the definition.
(Dickens' Ebenezer Scrooge is a miser)
'in film is erratic' is the wordplay.
'in' indicates the answer is hidden within the clue.
'MISER' can be found hidden inside 'film is erratic'.
(Other definitions for miser that I've seen before include "Pinchpenny" , "One's tight" , "not a spendthrift" , "Someone close" , "Tightwad, hoarder" .)