This four episode OVA series, originally released between October 1998 and March 2000, is the title which put studio Gonzo on the anime map. Prior to this work Gonzo had only animated cut scenes for a handful of video games, but its reputation soared afterwards on the strength of its effort here. (Gonzo also made the Melty Lancer anime during the same time frame, but it understandably had far less of an impact.) That reputation was built on the fact that this was the first all-digital anime series and the first to use 3D CG animation to anywhere near the level of prominence seen here, an occurrence which certainly turned some heads in the anime industry at the time. That put Gonzo on the leading edge of CG use in series anime, a position they would hold for several years afterwards.

But the series had much more than just its (for the time) cutting-edge use of CG to draw attention. At its core the story is a relatively simple post-apocalyptic tale about a flooded world and mankind having to struggle to survive against genetically-engineered humanoid creatures who could theoretically replace them. What makes it special, though, is its gloriously active and intense sub battles, and that more than anything else is probably responsible for it being a convention staple and featured show on Cartoon Network in the early 2000s. Close to half of the series' roughly two hour running time is tied up in either preparing for or waging these battles by full-sized and mini-subs against enemy whales, mecha, and submersible battleships, and in this aspect director Mahiro Maeda (who would later go on to helm Gankutsuou: The Count of Monte Cristo) turns in his finest work. The battles hum with a thrill factor and sense of motion that many other sub-based anime series only wish they could accomplish, to the point that even those who are not normally fans of sub battles may find themselves getting drawn in.

As strong as the series is in its action aspect, though, it is just as lacking on the writing front. Although the story does tell a more or less intact tale, it has the feel of something trimmed down from a project that was originally intended for 10-12 episodes. As a result the story has very little character development or even personality establishment, takes no time to explain anything, and has no room for anything more than minimalist plot, story, and emotional advancement. Even the underlying premise for the setting is never really properly explained, and all we ever really find out about Zorndyke's motives is that he lost faith in humanity due to a war-related incident and is perfectly willing to see it obliterated in favor of a new species. That he could accomplish what he has apparently on his own is mind-bogglingly beyond the limits of credulity if one stops and thinks about it for even a second. That the narrative jumps significantly between some of the episodes does not help, either.

But it looks good in the process. While some of the CG may seem crude by today's standards (especially in scenes where CG creations are blown up), in other places it stands up quite well and certainly trumps most CG-sporting productions from the first half of the 2000s. In one scene it even shows the CG design of the titular submarine take cosmetic damage from its conning tower being scraped by something. As innocuous as this may sound, this kind of detail simply doesn't happen in most series that use CG renditions of ships and/or mecha; CG-designed items are typically inviolate of visible damage unless major sections are removed or they are entirely destroyed. The ship designs are convincing without being spectacularly imaginative (and they certainly do not need to be), but the vaguely insectoid mecha impress much less. Human character designs are well-done but not especially distinctive beyond Mayumi, the female lead, who is featured on the cover and stands out because of her very short hair and a sleek, petite physique clearly angled more for sexiness than cuteness. Nonhuman designs are more creative, including mermaid-like creatures with catlike dispositions and behaviors, giant sentient whale-ships (hardly a novel concept but still interesting here), and a plethora of other beast-people. Good background art and generally excellent animation further contribute to a strong overall visual aesthetic. The violence is not particularly graphic, but the exposed breasts of the mermaid-cats are prominently-shown and Mayumi wears her jumpsuit zipped suggestively low in a couple of scenes.

The merits of the soundtrack are more nebulous. The series almost exclusively uses a jazz-driven score, even for its action scenes, in an effect not too dissimilar from Cowboy Bebop. However, the impact is very hit-or-miss in terms of how well it suits each scene. It works best in closer “Minasoko ni Nemure” by THE THRILL.

The English dub, provided by the long-since-defunct Coastal Carolina Sound Studios (Kite, Elf Princess Rane, the You're Under Arrest franchise), is well-cast and largely well-performed, with some performances arguably slight improvements on the Japanese originals. Especially effective is the electronically-distorted voice of Scott Simpson (the original English Keiichi Morisato) as the lead beastman Verg, and characters that are supposed to be black actually sound like they are. Sadly, the Blu-Ray release does not improve on the 2.0 stereo audio track used for the English dub in earlier releases; the Japanese dub has both the original 2.0 stereo and the vastly superior 5.1 remix. The English script takes some liberties, but not problematic ones.

The Blu-Ray release includes nearly two full hours of Extras. The most interesting one is a 21 minute interview with Satoru Ozawa, the manga-ka for the original 1960s manga from which this project takes its name (it otherwise bears very little resemblance to the original), which was apparently done for the Japanese Blu-Ray release. Among other things, he mentions that many fans of the original manga were initially appalled about how it got reimagined here but gradually came around to appreciate it over time, while he was quite pleased himself to see the new vision for his original ideas. Other Extras include an interview with the directors, a “Through The Creator's Eyes” segment which has commentary from several key production personnel, a 42 minute piece which looks primarily at the creation of the video game accompaniment to the series, a 15 minute amalgamation of newly-animated scenes from the game, a brief summary of the first three episodes dubbed in English, and a version of the closer which includes English credits and English-translated Japanese credits. (Each episode retains the original Japanese language closer.) The picture quality looks surprisingly crisp for a transfer from a pre-2000 source, but the compromise is that the original 4:3 aspect ratio is maintained, hence resulting in left and right-hand borders in HD displays.

Despite some dated-looking CG, on the whole Blue Submarine No. 6 stands up surprisingly well. Its writing flaws may have become more apparent over time, but it can still be a thrilling view and its roughly 120 minute total length keeps the story so compact that viewers do not have much opportunity to get bored. It is definitely still worth a look even for the new crop of anime fans.