Captain --, Jules Verne character (4)
I believe the answer is:
nemo
I believe this is a double definition.
'captain' is the first definition.
(character from 20,000 Leagues Under the Sea)
'jules verne character' is the second definition.
(I've seen this in another clue)
(Other definitions for nemo that I've seen before include "Jules Verne's submarine captain" , "Captain of the Nautilus" , "Fish sought in film" , "Finding -, animated film" , "commander for the Nautilus" .)