Terrible actor in trouble with debts (9)
I believe the answer is:
atrocious
'terrible' is the definition.
('atrocious' can be a synonym of 'terrible')
'actor in trouble with debts' is the wordplay.
'in trouble' indicates an anagram.
'with' is a charade indicator (letters next to each other).
'debts' becomes 'ious'.
'actor' anagrammed gives 'atroc'.
'atroc'+'ious'='ATROCIOUS'
(Other definitions for atrocious that I've seen before include "Foolish" , "Awful" , "Extremely wicked" , "Appallingly bad" , "Appalling" .)