Captain Nemo and I fighting to get freedom for slaves? (12)
I believe the answer is:
emancipation
'freedom for slaves?' is the definition.
(emancipation can mean being freed from slavery)
'captain nemo and i fighting' is the wordplay.
'and' means one lot of letters go next to another.
'fighting' indicates anagramming the letters (I've seen this in other clues).
'captain'+'nemo'='captainnemo'
'captainnemo' put after 'i' is 'icaptainnemo'.
'icaptainnemo' is an anagram of 'EMANCIPATION'.
'to get' acts as a link.
(Another definition for emancipation that I've seen is " release".)