Scenarist wary about getting into trouble (10)
I believe the answer is:
playwright
'scenarist' is the definition.
(thesaurus)
'wary about getting into trouble' is the wordplay.
'about' indicates an anagram.
'getting into' indicates putting letters inside.
'trouble' becomes 'plight' (I've seen this in other clues).
'wary' anagrammed gives 'aywr'.
'aywr' put into 'plight' is 'PLAYWRIGHT'.
(Other definitions for playwright that I've seen before include "Coward, for example" , "Shakespeare perhaps" , "16 dn of dramas" , "Author of dramas" , "Coward, for one" .)