Superhero gets cinema rocking (6)
I believe the answer is:
iceman
'superhero' is the definition.
(Iceman is one of the X-Men)
'cinema rocking' is the wordplay.
'rocking' indicates anagramming the letters.
'cinema' anagrammed gives 'ICEMAN'.
'gets' is the link.
(Other definitions for iceman that I've seen before include "eugene o'neill play'the......cometh'" , "assassin" , "Professional killer (US slang)" , "Cold character in cinema" , "'The ------ Cometh', 1939 play by Eugene O'Neill" .)