Very bad and very good intelligence? Very bad (10)
I believe the answer is:
villainous
'very bad' is the definition.
'very bad and very good intelligence?' is the wordplay.
'very' becomes 'v' (abbreviation).
'bad' becomes 'ill' ('ill' can be similar in meaning to 'bad').
'and' is a charade indicator (letters next to each other).
'very good' becomes 'ai'.
'intelligence?' becomes 'nous' (I've seen this in other clues**).
'v'+'ill'+'ai'+'nous'='VILLAINOUS'
(Other definitions for villainous that I've seen before include "dramatically bad" , "Nasty" , "criminal" , "very unpleasant" , "really bad" .)