Jules Verne's "20 000 leagues under the sea" was the very first book I've ever read on my own as a kid. It started my interested in sci-fi literature. This anime is proudly proclaiming inspiration by the book.
Basically it is Nautilus meets Space Battle Ship Yamato in Ghibli movie like story line. It's inspired by the story of Nautilus and captain Nemo indeed, but it manages to be its own thing. Especially towards the ending it seems to draw even from the Space Battle Ship Yamato. The characters and storytelling is very reminiscent of Ghibli movies.
The story follows adventures of young French boy Jean, who is aspiring to be great inventor, and young exotic-looking orphan girl Nadia, who is a circus acrobat and the only memento of her origin is a strange gem called Blue Water. Jean falls in love with Nadia at first sight, but she does reciprocate his feelings only very gradually in a girly confused way. At times I really felt sorry for Jean. Nadia is very pretty girl, but she acts like a brat quite lot. Jean is very optimistic albeit geek absorbed by his inventions, on the other hand Nadia is stubborn and quick to despair in hard situations. Pretty much all key characters in the series are multi-layered, having respective strengths weaknesses. Moreover their age and sex is taken into account as well. This is one of the best things about the series. Initially they are pursued by a noble lady Grandis, who wants the jewel, and her two henchmen Sanson and Hanson.
Minor spoilers in the following paragraph (skip to the next paragraph to avoid spoilers).
Grandis and her henchmen will join with the main protagonist to fight the true main antagonist of the series Gargoyle. Grandis, who seems initially as mere comical antagonist, becomes even a motherly figure to Nadia, a mentor of womanhood. I really liked this development of characters. Similarly with Sanson and to some extent Hanson, which help Jean to grow. Captain Nemo is a tragic character, man fighting lone battle with only a small crew against Gargoyle, who has an army of henchmen and plenty of resources. Like captain Okita in Space Battleship Yamato, he sits in his chair giving commands. Outside battle he is a man of few words, keeping to himself. There is nothing much to like or dislike about him for that very reason. Electra, the second in command, is a somewhat tragic figure too. Gargoyle is a classic villain. He is not a likeable character. There is no honour or morality to him as he treats outsider. He does believe he is doing this for “his people” and to restore them to the proper place in the world. He doesn’t hesitate to sacrifice even his men or to kill them as punishment in case they fail in a task. I liked as character little Maria. She brings child’s perspective on things. A very honest and straightforward. By the end she and Grandis were for me overall the most likeable characters in the series.
The main gist of story is not original. There has to be many sci-fi stories adopting same sci-fi elements and premises about the world. Biblical references unsurprisingly are quite absurd, but it’s not that different from any mainstream sci-fi. However the story improves a lot on the dryness of the original Jules Verne. As I said, I like the story except it being somewhat unoriginal sci-fi cliché. One more thing there is a part in the story, which smells of filler arc. I can’t say what in order to avoid spoilers, but it is in the second half the series.
The animation is 90s’. I’ve nothing against it. It was ok. Reminded my bit of Ghibli style, except less polished. It’s to be expected in a television series.
The music is good, especial the opening, main theme, "Blue Water". It’s the initial reason how I found out this show to begin with. It’s just amazing and very catchy. I’ve listened to it for a week or two over, over and over again.
Overall I do recommend this anime. The only shame that the first half is overall better, than the second. The finale is good.