Emissary, courier (9)
I believe the answer is:
messenger
I believe this clue is a double definition.
'emissary' is the first definition.
(I've seen this before)
'courier' is the second definition.
(I know that courier can be written as messenger)
(Other definitions for messenger that I've seen before include "Communication carrier" , "One who bears a communication" , "The role of Hermes or Mercury?" , "Person carrying information to another" , "He brings the news - don't shoot him" .)