Detectives going back on record is nothing irregular (8)
I believe the answer is:
episodic
'irregular' is the definition.
(thesaurus)
'detectives going back on record is nothing' is the wordplay.
'detectives' becomes 'cid' (**).
'going back' says the letters should be written backwards.
'on' is a charade indicator (letters next to each other).
'record' becomes 'ep'.
'nothing' becomes 'o' (looks like zero - 0).
'cid' backwards is 'dic'.
'ep'+'is'+'o'='episo'
'dic' put after 'episo' is 'EPISODIC'.
(Other definitions for episodic that I've seen before include "Occurring at irregular intervals" , "Presented in sections" , "Occurring irregularly - is copied accordingly" , "Is copied in irregular occurrence" , "Occurring irregularly or in instalments" .)