Unscrupulous person: Tweedledum say? (4,3)
I believe the answer is:
wide boy
'tweedledum say?' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.
'unscrupulous person' is the wordplay.
'unscrupulous' becomes 'wide' (I can't explain this - if you can you should give a lot more credence to this answer).
'person' becomes 'boy' (boy is a kind of person).
'wide'+'boy'='WIDE-BOY'
Can you help me to learn more?
(Other definitions for wide boy that I've seen before include "Tweedledum, for instance" , "A rather unscrupulous person" , "Spiv" , "petty young criminal" .)