Wee drink before a theatrical production (5)
I believe the answer is:
drama
'theatrical production' is the definition.
(a dramatic work)
'wee drink before a' is the wordplay.
'wee drink' becomes 'dram' (small amount of alcohol).
'before' means one lot of letters go next to another.
'dram'+'a'='DRAMA'
(Other definitions for drama that I've seen before include "Emotional situation" , "Play; emotional event" , "theatre performance" , "Play; exciting situation" , "Play (as a genre)" .)