Walker returns, in summary (5)
I believe the answer is:
recap
'summary' is the definition.
(I know that recap is a type of capitulation)
'walker returns' is the wordplay.
'walker' becomes 'pacer' (I've seen this before).
'returns' says the letters should be written backwards.
'pacer' reversed gives 'RECAP'.
'in' acts as a link.
(Other definitions for recap that I've seen before include "Review" , "Summarising statement" , "Restate" , "In brief, go over the main points again" , "Go over study material again" .)