Play organ before holiday audience (10,5)
I believe the answer is:
heartbreak house
'play' is the definition.
(George Bernard Shaw play)
'organ before holiday audience' is the wordplay.
'organ' becomes 'heart' (heart is a kind of organ**).
'before' is a charade indicator (letters next to each other).
'holiday' becomes 'break' (I've seen this before).
'audience' becomes 'house' (house is a kind of audience).
'heart'+'break'+'house'='HEARTBREAK HOUSE'
(Other definitions for heartbreak house that I've seen before include "Play" , "Theatrical work" .)