Spartakus and the Sun Beneath the Sea (Les mondes engloutis) was a wonderfully crafted animated series that aired sometime in the 80s. It told the story of a civilization that survived a great cataclysm and moved to the center of the earth. These people, the Arkadians, thrived under the power of their artificial sun, The Tehra, until one day it began to fail. In desperation, the Arkadians broke the ancient law and entered the Forbidden Archives to search for an answer. They used their special powers and created a messenger to the people above, naming her Arkana. She meets up with Matt and Rebecca, two ordinary kids from the surface world, Bic and Bac, two strange anteaters from Arkadia, and Spartakus, a mysterious warrior. Together they search the worlds of the strata for a way to save a people and possibly the world. This cartoon is quite possibly one of the greatest animated series of all time. A French cartoon, Spartakus and the Sun Beneath the Sea was very stylized in its animation and way of storytelling. Instead of bright pastel colors and deep lines, the colors were muted with mixtures of earthy tones. And the cartoon had themes of mysticism and surrealism. Yet its deep history and strong characters made the show appealing to people of all ages and tastes.
Guided by a mysterious mute woman, the group ascends a large tower filled with recorded knowledge from throughout history, but someone is trying to keep them from reaching the top.
The travelers are caught in the web of a giant spider. Bic and Bac are held captive by a tribe of their anteater cousins for their fire-making ability.
The travelers investigate the stratum where the People of the Deep mysteriously vanished long ago. To help Tehrig stay on course in this area, which has magnetic disturbances, they create a fake competitor to FIPIRATE, tricking the pirates into increasing their broadcast signal strength. Of course it also causes the pirates to put on a huge impromptu concert for all the rogues of the strata.
The group investigates a city closed in by giant walls and are captured by the army of Iron Men, who terrorize its citizens. With the help of an eccentric genius named Uncle Albert, they plot to help the people escape.
The travelers discover an abandoned city that was once inhabited by the Arkadians who built the Tehra. Rainbow is here, too, and he wants the secrets of the Arkadians, as well as Arkana, for himself.
Tehrig is stuck in an ancient trap designed to disable ships run by artificial intelligence. Fortunately, the pirates are vacationing nearby, and Rebecca, Bic, and Bac try to steal the pirate ship to rescue their friends, with a little help from Ringnar's mischievous nephews.
Tehrig lands on an island inhabited by slow-witted dodo birds that can draw people into their dreams of flight. Rebecca gets lost after the pirates try to catch the birds and finds herself at the home of Alice, who lives alone with her memories of Wonderland.
Tehrig is trapped by Arachne's web, and to free his friends, Spartakus has to board the ghost ship Araukania, where he agrees to guide the ship on its final journey to the Gateway to Dawn.
The travelers are aided in their search for an underground vein of metal that may be auracite by a powerful but suspicious magician called the Manitou. Along the way, they encounter a Cherokee from the surface who is looking for a new home for his people.
While exploring a cave, Matt and Rebecca meet Arkana, who tells them of her mission. When the pirates attack, they are rescued by a mysterious warrior named Spartakus.
Tehrig is swept away by the powerful currents of the River of Time. The group finds themselves in a land occupied by a primitive tribe that is being threatened by the machines of an advanced civilization from the stratum above. Meanwhile, the children of Arkadia are trying to fix the entrance to the Archives, which has rusted shut.
The group returns to Arkadia to attempt to free the Prisoners of Lost Time but discover that the Tehra will never be permanently restored until a riddle is solved and a second auracite is found.
Matt and Rebecca discover a parallel world that resembles their hometown, where a war has been raging for countless years. The only way to stop the fighting is to show both sides proof of Arkadia's existence.
Spartakus returns to Arkadia with the Prisoners of Lost Time. Together, they discover the truth about the second auracite and Arkadia's original purpose. Matt and Rebecca return home as the Arkadians fulfill their destiny.
Believing Arkana to be long-lost love, a mad scientist sends Tehrig back in time through the group's many adventures, in an attempt to bring her back to him. This episode is what's often called a "clip show", since it consists mostly of scenes from previous episodes.
The group finally reach Arkadia and try to solve the mysteries of the Tehra. Spartakus discovers that his wristguard may hold the key.
The group is forced to battle in a real-life chess match against some of their most fearsome enemies.
Matt follows a devilish trickster and his supernatural pets, a giant eagle and a teleporting snake, on a dangerous quest to find "the gold at the earth's core", thinking it may be the second auracite. Spartakus, knowing that no one has ever returned from the journey, tries to stop him.
While crossing the deserts of Barkar, Spartakus recalls the incident that took away his family and forced him into slavery, his life as a gladiator, and the bitter reunion with his long-lost brother.
Ringnar holds Tehrig prisoner, forcing his triggies to build new luxury high-rise apartments for the pirates. When Nasty Max discovers what Ringnar is up to, the two begin a power struggle for the control of Tehrig, the tower, and the pirates' loyalties.
The travelers meet Tutankhaton, who is about to become pharaoh, and are caught up in a plot by the boy's uncle and the Priests of Amon, who want to seize power and return to worship of the old gods.
When the pirates capture just about everyone on the seas, the group find themselves prisoners in the hold of the pirates' ship. Meanwhile, Bic and Bac have to deal with being forced to work as Massmedia's musicians and trying to recover Spartakus' wristguard from the pirates' casino, all while trying to avoid nasty pickpockets.