An important character in the school play (3,9)
I believe the answer is:
the caretaker
'play' is the definition.
(Harold Pinter play)
'an important character in the school' is the wordplay.
I cannot really see how this works, but
'an' could be 'a' and 'a' is found in the answer.
'character' could be 'he' (he is a kind of letter of the alphabet) and 'he' is present in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for the caretaker that I've seen before include "stage production" , "Drama" , "1960 Pinter play" , "Play by Harold Pinter" .)