Son is spy producing summary (8)
I believe the answer is:
synopsis
'summary' is the definition.
(I know that synopsis is a type of summary)
'son is spy producing' is the wordplay.
'producing' indicates anagramming the letters.
'son'+'is'+'spy'='sonisspy'
'sonisspy' with letters rearranged gives 'SYNOPSIS'.
(Other definitions for synopsis that I've seen before include "rundown?" , "Precis or summary" , "sketch" , "Pr?cis, abstract" , "General summary" .)