Everyone into wicked tune (6)
I believe the answer is:
ballad
'tune' is the definition.
(type of song)
'everyone into wicked' is the wordplay.
'everyone' becomes 'all' (I've seen this before).
'into' is an insertion indicator.
'wicked' becomes 'bad' (associated in meaning).
'all' put inside 'bad' is 'BALLAD'.
(Other definitions for ballad that I've seen before include "delivered by singer" , "Narrative song of popular origin" , "Narrative song with a recurrent refrain" , "Simple song or poem" , "Slow romantic song" .)