Bet against queen making film (5)
I believe the answer is:
layer
'film' is the definition.
(film can mean a thin layer of something)
'bet against queen' is the wordplay.
'bet' becomes 'lay' (I've seen this in another clue).
'against' means one lot of letters go next to another.
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'lay'+'er'='LAYER'
'making' is the link.
(Other definitions for layer that I've seen before include "Early (anag.)" , "Stratum, tier" , "Thickness of material or earth - relay it" , "course" , "plate?" .)