20,000 Leagues Under the Sea (Barnes & Noble Classics Editions)

Verne returned to the theme of an outlaw submarine captain in his much later Facing the Flag. That book's main villain, Ker Karraje, is a completely unscrupulous pirate acting purely and simply for gain, completely devoid of all the saving graces which gave Nemo--for all that he, too, was capable of ruthless killings--some nobility of character.