Doctor Brown on Italian thriller (8)
I believe the answer is:
whodunit
'thriller' is the definition.
(thesaurus)
'doctor brown on italian' is the wordplay.
'doctor' becomes 'who' (I've seen this in other clues).
'brown on' becomes 'dun' (dun is a kind of brown. I am not sure about the 'on' bit.**).
'italian' becomes 'it'.
'who'+'dun'+'it'='WHODUNIT'
Can you help me to learn more?
(Other definitions for whodunit that I've seen before include "thriller" , "Crime mystery novel, play or film" , "Informally, a detective story or play" , "murder investigation" , "Crime story (colloq.)" .)