Agitator in East London ready on complex brief (9)
I believe the answer is:
firebrand
'agitator' is the definition.
(I've seen this before)
'east london ready on complex brief' is the wordplay.
'east london ready' becomes 'rand' (South African currency - East London is an SA city).
'on' says to put letters next to each other.
'complex' is an anagram indicator.
'brief' is an anagram of 'fireb'.
'rand' put after 'fireb' is 'FIREBRAND'.
'in' acts as a link.
(Other definitions for firebrand that I've seen before include "Agitator" , "Rabble-rouser" , "One who stirs up trouble" , "Troublemaker" , "Energetic person often fomenting trouble" .)