Superhero in club with servant (6)
I believe the answer is:
batman
'superhero' is the definition.
(DC superhero)
'club with servant' is the wordplay.
'club' becomes 'bat' (as in sporting equipment).
'with' means one lot of letters go next to another.
'servant' becomes 'man' (man is a kind of servant).
'bat'+'man'='BATMAN'
'in' is the link.
(Other definitions for batman that I've seen before include "Tender" , "Comic/film superhero" , "Caped superhero" , "Officer's servant; the Caped Crusader" , "Comic strip character" .)