I personally want to give title "Cliffhanger" to this anime. Like 90% of the episodes ended up with a cliffhanger... Don't get me wrong, I actually loved this. I kind of regret it aired before I started watching anime, because this anime had enormously huge variety of topics to discuss. Every episode was very different from the previous one and many turnarounds happened. I was sometimes even confused so who's right and who's wrong, who's the ally and who's the enemy... Great mind games (not as great as Code Geass and Death note tho) were played during the episodes and it was almost impossible to predict what will be their next move.
Basically this anime starts with 21st century's battle ship leaving the port for some training exercises and encountering some sort of anomaly that sends them back in time to 1942 year (60 years ago). This was the time when Japan were in a war against USA. The next 26 episodes of this anime is how the whole crew struggles to avoid any contact with the people from those years so that they wouldn't change the history.
However, can you actually avoid everyone when you are in the middle of a war? Obviously not...you need food, fuel and other things to survive... and this is were the fun begins... The battle ship from 21st century has such advanced weapons that are enough to destroy the whole USA army (it's realistic, in 60 years weapons do advance that much). Moreover, they know the whole history of this war. In other words they know every movement of both Japan's and USA's armies and what were the turning points of war and just basically they were overpowered. However, they didn't want to participate in this war at all, this was not their war, so this what makes the anime so great... Just how they try to avoid any minimal contact with anyone and what happens when they finally get spotted by both Americans and Japanese people...
The realism of this show was incredible if you don't think about this "time travelling thing". Zipang did a good job portraying the moral issues and how they were dealt with within the crew and their opponents/allies. However, those 26 episodes weren't enough to finish the series. They ended up on another big cliffhanger. Of course, there is manga, but... the disappointment of not having a sequel is huge.
