A show presented before the show (7)
I believe the answer is:
preview
'a show' is the definition.
(I have seen 'early show' mean 'preview' so perhaps 'show' could also mean 'preview')
'before the show' is the wordplay.
'before' becomes 'pre' (prefix meaning 'before').
'the show' becomes 'view' (I am not sure about this - if you are sure you should believe this answer much more).
'pre'+'view'='PREVIEW'
'presented' is the link.
Can you help me to learn more?
(Other definitions for preview that I've seen before include "Foretaste" , "Early sight of something coming" , "A showing before opening night" , "Preliminary showing" , "An advance look" .)