Captain Nemo

Captain Nemo is one of the four main characters and the main antagonist in Disney's 1954 film, 20,000 Leagues Under the Sea. He is the captain of the Nautilus. In the Disney film, he was portrayed by the late James Mason.

20,000 Leagues Under the Sea
After the Nautilus was constructed, the prisoners became its crew, with Nemo becoming the Captain, they established a base on the Island of Vulcania. For several months the Nautilus travelled throughout the oceans, attacking numerous ships. After one such encounter, three survivors arrived aboard the Nautilus, Professor Aronnax, Conseil, and Ned Land. Nemo quickly invited Arronax to join him and reluctantly took Conseil and Ned as prisoners. He hoped to use Arronax as an emissary in order to allow Nemo to share his secrets with the world.

The Nautilus continued it's travels across the oceans. Nemo got to know Arronax better, and showed him some of his past. Ned continued to irritate Nemo due to his constant attempts to escape.

Eventually the Nautilus returned to the Island of Vulcania, only to discover it to have been invaded by soldiers because Ned had secretly released several bottles containing the location of the Island. Nemo decided to prevent the soldiers from finding his secrets, and left the nautilus to destroy the base. The attempt was successful, but as Nemo re-entered the Nautilus, he was unexpectedly shot in the back. Nemo died shortly after, gaining one last glimpse of the ocean.

Disney Parks
Captain Nemo played a significant role in 20,000 Leagues Under the Sea. While he was not actually seen, his voice would fequently be heard speaking to other crew members.

In Tokyo DisneySea's Mysterious Island, the story is set in an alternate path from the movie where Nemo didn't die, but instead has opened up to the world and allowed visitors to explore Vulcania in the name of scientific curiosity.

Personality
Nemo has always been a mysterious character. He is a brilliant genius, having created the Nautilus in the middle of the 19th Century, and powered it using a nuclear reactor. He willingly attacks ships, but does show guilt.

Nemo also loves the Ocean and made it his home. All his food comes from some form of sea life. He also keeps various preserved samples of various sea creatures, and even has a pet sea lion, Esmeralda.

Trivia

 * In the original Jules Verne novel, Nemo's fate is never made clear. In fact, an older Nemo actually appeared in a later novel, The Mysterious Island, where he is revealed to have survived the ending of 20,000 Leagues Under the Sea and is now the only surviving member of the crew of the Nautilus. He secretly helps a group of stranded Civil War veterans who unknowingly crash a hot air balloon at the home port of the Nautilus.
 * Actor Gregory Peck reportedly auditioned to play Nemo, but lost the part to James Mason.
 * Nemo, the titular character from Finding Nemo and Nemo, from the Rescue Rangers, may have been named after Captain Nemo.
 * Captain Finn, from the Rescue Rangers, may have been based on him.