Flying squad eyes new criminal (7)
I believe the answer is:
sweeney
'flying squad' is the definition.
Both the answer and definition are singular nouns.
Maybe there's a link between them I don't understand?
'eyes new criminal' is the wordplay.
'criminal' indicates anagramming the letters.
'eyes'+'new'='eyesnew'
'eyesnew' with letters rearranged gives 'SWEENEY'.
Can you help me to learn more?
(Other definitions for sweeney that I've seen before include "------- Todd, the 'demon barber of Fleet Street'" , "The flying squad" , "London police" .)