Theatre backer, not bold, abandoned play (3,9)
I believe the answer is:
the caretaker
'play' is the definition.
(Harold Pinter play)
'theatre backer not bold abandoned' is the wordplay.
'not' suggests deleting specific letters.
'bold' becomes 'b' (abbreviation).
'abandoned' is an anagram indicator.
'theatre'+'backer'='theatrebacker'
'theatrebacker' with 'b' taken out is 'theatreacker'.
'theatreacker' with letters rearranged gives 'THE CARETAKER'.
(Other definitions for the caretaker that I've seen before include "Drama" , "Play by Harold Pinter" , "1960 Pinter play" , "stage production" .)