Captain Finn

Captain Finn is a fish, who found an old submarine (resembling the Nautilus) and desired to take revenge on humanity. However, even a hand picked, fin picked, crew which included All Hands, Mr. Starfish and some other underwater creatures didn't bring Captain Finn success. He appeared in the episode "A Creep in the Deep".

Trivia

 * His desire to take revenge on humanity, his hatred of the outside world, his love of the sea, his role as Captain is based on Captain Nemo from 20,000 Leagues Under the Sea.
 * His submarine resembles Captain Nemo's submarine, the Nautilus.