Before you read this movie, read these stories first in this order:
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-777784461
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-2-777908342
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-3-777909525
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-4-777911708
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-5-777913752
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-6-777914203
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-7-777916164
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-8-777916946
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Special-Words-Of-Beauty-781740256
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Special-White-Day-Methods-786571638
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Special-Secrets-Revealed-788053811
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-9-823488189
https://www.deviantart.com/kid-z4p/art/CardCaptor-Chronicles-Episode-10-831200209
https://www.deviantart.com/kid-z4p/art/Kinomoto-Chronicles-1-835827146
https://www.deviantart.com/kid-z4p/art/Kinomoto-Chronicles-2-835833527
https://www.deviantart.com/kid-z4p/art/Kinomoto-Chronicles-3-835847220
https://www.deviantart.com/kid-z4p/art/Kinomoto-Chronicles-4-835855951
Have you read them? If so, proceed with this movie.
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SpongeBob, Sakura, Squidward, Touya, Mr. Krabs, and Fujitaka have discovered a coin bearing the Greek letter Sigma in ruins of Mycenae and barely escaped near-death by triggering a booby trap. Returning home, they discover that the coin could lead them to the lost city of Duohndia, the alleged sister city of Atlantis.
In legend, Duohdia was said to be the first city made from the remnants of where Atlantis once stood, thus making it the sister city. Their primary source of heat came from the same underwater volcanos that sunk Atlantis, but just like Atlantis, Duohdia was also destroyed by said volcanos, thus beginning the legend of the Atlantean Curse. Many years later, a legendary adventurer, named Saurem, set out to save Duohdia's history and existence, using a book made of platinum and the Scepter of Guidance, the very device used to the lost remnants of Duohdia, but during his expedition, he had disappeared, but the Scepter was found years later by a cult that worshipped Saurem, who kept it hidden, using multiple boxes to confuse anyone who tried to take it.
Mr. Krabs and Professor Darius Hughes, an old friend of Fujitaka, and a convinced scholar who believes the legend of Duohdia is real, think that the coin is the key to solving Saurem's riddle (which he first heard of in dome caves of Exeter where early Christians hid from the Romans). The Towa University Board grants Hughes the funds to pursue an expedition, but Harrison Simmons, a professor who bears a strong dislike towards Hughes and Krabs, and believes that Duohdia never existed, angrily rants about their decision, and suggests that Hughes be booted out. When the Board refuses to do so, Simmons decides to petition for it.
