Twenty Thousand Leagues Under the Sea is a classic science fiction novel by French writer Jules Verne, published in 1870 under the title Vingt mille lieues sous les mers. The novel is about the fictional Captain Nemo and his submarine, Nautilus, as seen by one of his passengers. The story was written before modern sea-going submarines were a reality. It is narrated by Professor Pierre Aronnax, a noted marine biologist, who is accompanied by his faithful assistant Conseil and by a Canadian harpooner named Ned Land. As the story begins, a mysterious "sea monster", theorized by some to be a giant narwhal, is sighted by ships of several nations; an ocean liner is also damaged by the creature. The United States government finally assembles an expedition to track down and destroy the menace. Since Aronnax happens to be in New York City at the time and is a recognized expert in his field, he is invited at the last minute to go along, and he accepts. Master harpoonist Land is also brought on board.

Some of Verne's ideas about the not-yet-existing submarines which were laid out in this book turned out to be prophetic (such as the high speed and secret conduct of today's nuclear attack submarines), and (with diesel submarines) the need to surface frequently for fresh air.Verne borrowed the name "Nautilus" from one of the earliest successful submarines, built in 1800 by Robert Fulton, who later invented the first commercially successful steamboat. The word itself is after the chambered nautilus, a kind of mollusk. Verne can also be credited with glimpsing the military possibilities of submarines, and specificially the danger which they possessed for the naval superiority of the British Navy, composed of surface warships. The fictional sinking of a ship by Nemo's "Nautilus" was to be enacted again and again in reality, in the same waters where Verne predicted it, by German U-boats in both World Wars.

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 void of all the saving graces which gave Nemo - for all that he, too, was capable of ruthless killings - some nobility of character.Like Nemo, Ker Karraje plays "host" to unwilling French guests - but unlike Nemo, who manages to elude all pursuers, Karraje's career of outlawry is decisively ended by the combination of an international task force and the rebellion of his French captives. Though also widely published and translated, it never attained the lasting popularity of "Twenty Thousand Leagues". More similar to the original Nemo, though with a less finely worked-out character, is Robur in Robur the Conqueror - a dark and flamboyant outlaw rebel using an aircraft instead of a submarine.

The Mysterious Island - The novel is a sequel to Verne's famous Twenty Thousand Leagues Under the Sea and In Search of the Castaways, though thematically it is vastly different from those books.
In Search of the Castaways (original title Les Enfants du capitaine Grant, "The Children of Captain Grant") is a Science fiction novel published in 1867-1868. The original edition, by Hetzel, contains a number of illustrations.