Nadia: The Secret of Blue Water (ふしぎの海のナディア, Fushigi no Umi no Nadia) is a classic Japanese anime television series created by the renowned studio Gainax and directed by Hideaki Anno, who is also famous for his work on Neon Genesis Evangelion. The series, which originally aired from 1990 to 1991, is heavily inspired by the works of the 19th-century French author Jules Verne, particularly his novels Twenty Thousand Leagues Under the Seas and The Mysterious Island. These literary influences are evident in the show's themes of exploration, advanced technology, and the enigmatic character of Captain Nemo, who plays a significant role in the story.

    The anime follows the adventures of two main protagonists: Jean, a young and brilliant inventor with a passion for science, and Nadia, a mysterious girl who was once a circus performer. Nadia possesses a unique blue jeweled pendant, which becomes the focal point of the story as it holds a secret tied to her origins and a powerful ancient civilization. The series begins with their chance meeting at the 1889 Paris World's Fair, where they are pursued by a group of villains seeking the pendant. This sets them on a thrilling journey across the globe, filled with danger, discovery, and intrigue.

    As the story unfolds, Jean and Nadia encounter the futuristic submarine, the Nautilus, commanded by the enigmatic Captain Nemo. The Nautilus and its crew become central to the narrative, as the protagonists join forces with Nemo to combat the nefarious organization known as Neo Atlantis, which seeks to exploit the power of Nadia's pendant for world domination. The series masterfully blends elements of science fiction, steampunk, and adventure, while also exploring deeper themes such as identity, morality, and the consequences of technological advancement.

    Nadia: The Secret of Blue Water is celebrated for its rich storytelling, memorable characters, and stunning animation, which was groundbreaking for its time. Despite some production challenges and a few episodic detours, the series remains a beloved classic in the anime world and a testament to Hideaki Anno's creative vision. It has also been praised for its homage to Jules Verne's legacy, bringing his imaginative worlds to life in a way that resonates with both younger audiences and longtime fans of science fiction.

    The series explores themes of identity, belonging, and the consequences of human ambition. Environmentalism and the dangers of unchecked technological progress are also prominent, reflecting the influence of Jules Verne's works and the show's broader philosophical questions. Fans of Neon Genesis Evangelion may see some precursors to the later series as The Secret of Blue Water discusses identity, psychology, and the impact of technological progress. In fact, Nadia's troubled production directly led to the creation of Evangelion, which was originally meant as a sequel to the earlier series.

    The show consists of 39 episodes, which can be divided into distinct story arcs. The first half focuses on the initial adventures and the introduction of the Nautilus, while the second half delves deeper into the conflict with Neo-Atlantis and the mysteries of Nadia's pendant and her own identity. Some episodes, particularly in the middle of the series, are more episodic and filler-like, dubbed notoriously as the "Island Arc" and "Africa Arc." These episodes are widely disliked and infamous, even referenced in other shows like Gintama. Your mileage may vary with these episodes - while the animation and storytelling drops in quality, particularly in the main cast of characters, they also provide important worldbuilding information that may be missed by viewers who skip these episodes. Upon my first viewing, I had no knowledge of any of this, so I watched through both arcs. I'm actually rather fond of the Island Arc despite its many flaws. It's a bizarre, Saturday-morning-cartoon-like interlude that some people may come to resent, but I had a lot of fun watching them (even though I'm not too keen on how the arc handled Nadia's character). As for the Africa Arc, however... It's racist and weird and I don't like it. But again, YMMV! It's up to you whether you like the filler episodes, if you even decide to watch them at all. I do usually skip both arcs to maintain the show's tone, but sometimes I feel like watching the island episodes for fun!