Disclosure from devious spy, a place with nothing hidden (10)
I believe the answer is:
apocalypse
'disclosure' is the definition.
(I have seen 'prophetic disclosure' mean 'apocalypse' so perhaps 'disclosure' could also mean 'apocalypse')
'devious spy a place with nothing hidden' is the wordplay.
'devious' is an anagram indicator.
'with nothing' becomes 'o' (I've seen this in other clues).
'hidden' is an insertion indicator.
'spy'+'a'+'place'='spyaplace'
'spyaplace' is an anagram of 'apcalypse'.
'apcalypse' enclosing 'o' is 'APOCALYPSE'.
'from' acts as a link.
(Other definitions for apocalypse that I've seen before include "Revelation" , "terrible event" , "prophetic disclosure" , "This last book" , "Catastrophic event" .)