Under surveillance — and irritated! (6)
I believe the answer is:
bugged
I believe this clue is a double definition.
'under surveillance' is the first definition.
(a bug is a secret microphone)
'irritated' is the second definition.
(thesaurus)
'and' is the link.
(Other definitions for bugged that I've seen before include "Softly glowing" , "Fitted with hidden microphone for eavesdropping" , "Of room, fitted with secret microphones" , "Description of room fitted with illegal listening devices - infested?" , "Annoyed" .)