Worked with detectives to get rank (6)
I believe the answer is:
rancid
'rank' is the definition.
(thesaurus)
'worked with detectives' is the wordplay.
'worked' becomes 'ran' (running is a kind of working).
'with' says to put letters next to each other.
'detectives' becomes 'cid'.
'ran'+'cid'='RANCID'
'to get' is the link.
(Other definitions for rancid that I've seen before include "Sour like stale fat" , "Stinking" , "Sour, rotting" , "Rotten; high" , "Tasting or smelling sour, butter say" .)