Always turning up before bad deal is exposed (8)
I believe the answer is:
revealed
'is exposed' is the definition.
(I've seen this before)
'always turning up before bad deal' is the wordplay.
'always' becomes 'ever' (synonyms).
'turning up' says the letters should be written in reverse.
'before' says to put letters next to each other.
'bad' indicates an anagram.
'ever' backwards is 'reve'.
'deal' is an anagram of 'aled'.
'reve'+'aled'='REVEALED'
(Other definitions for revealed that I've seen before include "Like the religion" , "'Made known, disclosed (8)'" , "Made clear and visible" , "Discovered" , "Exposed" .)