Rousing being part of espionage plot, we're told (9)
I believe the answer is:
inspiring
'rousing' is the definition.
(thesaurus)
'being part of espionage plot we're told' is the wordplay.
'being part of espionage plot' becomes 'in spy ring'.
'we're told' shows a homophone (sound like).
'inspyring' sounds like 'INSPIRING'.
(Other definitions for inspiring that I've seen before include "Motivation" , "Filling with confidence, stimulating to achievement" , "Breathing (that's encouraging!)" , "Animating; uplifting" , "Impressive" .)