Film role in bag with support of American (9)
I believe the answer is:
spartacus
'film' is the definition.
(I've seen this before)
'role in bag with support of american' is the wordplay.
'role' becomes 'part' (synonyms).
'in' indicates putting letters inside.
'bag' becomes 'sac' (I've seen this before).
'with support of' is a charade indicator (letters next to each other) (some letters go beneath or support others).
'american' becomes 'us' (abbreviation for United States).
'part' put into 'sac' is 'spartac'.
'spartac'+'us'='SPARTACUS'
(Other definitions for spartacus that I've seen before include "Leader of a gladiators' revolt in 73BC" , "Roman slave leader - 1954 ballet composed by Aram Khachaturian - 1960 film starring Kirk Douglas" , "1960 gladiator film" , "Old fighter" , "Thracian who led the 73 BC slave revolt against Rome" .)