Dope dares to upset gangster (9)
I believe the answer is:
desperado
'gangster' is the definition.
(I've seen this before)
'dope dares to upset' is the wordplay.
'to upset' indicates anagramming the letters.
'dope'+'dares'='dopedares'
'dopedares' anagrammed gives 'DESPERADO'.
(Other definitions for desperado that I've seen before include "Bold outlaw on the American frontier" , "Road speed (anag.)" , "Reckless criminal" , "Bravo" , "Bandit, outlaw" .)