Peril not unusual for crime fighters (8)
I believe the answer is:
interpol
'crime fighters' is the definition.
(I've seen this before)
'peril not unusual' is the wordplay.
'unusual' is an anagram indicator.
'peril'+'not'='perilnot'
'perilnot' is an anagram of 'INTERPOL'.
'for' acts as a link.
(Other definitions for interpol that I've seen before include "Joined forces" , "International law enforcement agency" , "investigators" , "Multinational crime fighters" , "International co-ordinating police body" .)