This second chapter goes into redress (2,4)
I believe the answer is:
at once
'this second' is the definition.
(I've seen this in another clue)
'chapter goes into redress' is the wordplay.
'chapter' becomes 'c' (abbreviation).
'goes into' means one lot of letters goes inside another.
'redress' becomes 'at one' (I've seen this in another clue).
'c' going inside 'atone' is 'AT ONCE'.
(Other definitions for at once that I've seen before include "from the kick-off" , "This instant - no delay (2,4)" , "Octane (anag)" , "'Immediately (2,4)'" , "'Without delay (2,4)'" .)