A three episode 1989 OVA adaptation of an 18 volume long manga that published between 1987 to 1991, Umi no Yami Tsuki no Kage is a story about identical twin sisters, Rumi and Ruka who survive the exposure to an uncovered burial ground in a cave with deadly gases that kills every one of their classmates present but grants the twins superpowers that correspond to the cycles of the moon. One of the sisters, Rumi goes insane after she wakes up and decides to stop at nothing to acquire the boy both sisters like, Katsuyuki-kun even if it means killing anyone that stands in her way, including her sister.

The premise of this anime is fairly interesting and is what caught my attention while browsing for stuff to download, but unfortunately the anime is a lot more underwhelming in practice. There is no progression to Rumi’s insanity for example, she just faints from the cave incident and when she wakes up she is already an insane psychopath willing to use her newfound powers to whatever she decides. The other characters are not any better as they can be most generously described as horror movie stupid and make the dumbest decisions possible, worst of all they don’t take Rumi with the seriousness the situation would deserve until she has already killed a lot of people.

It is also definitely not the best looking OVA I have watched, it does not look ugly or anything necessarily, but I did find some of the visual effects weird like how Rumi turns entirely blue when using her powers or the funny way the characters just stiffly floated in the air and did this awkward hovering while chasing the other characters.

Worst of all is the fact that the anime does not conclude things as obviously the manga was still not finished at the time it was made and as such nothing is really resolved. You basically have a large portion of the town being mind controlled like puppets by Rumi (it is one of the powers she has) and the anime just ends with basically Katsuyuki daring her to take his life if she wants him so much saying “she can have his body but not his heart“, and to which Rumi actually chickens out and runs away as the anime closes without either having dealt with her or the puppets.

So why should anyone watch this? It is very short about an hour long with all 3 episodes if you don’t include the openings and endings, so the basic interest of the premise is more than enough to last you for that hour before you would get bored by it, also it has this dumb 80’s horror feeling going for it which can be appealing to you, it is the kind of anime that in many ways becomes more entertaining by its flaws, such as the dumbness of the characters contributing to entertainment. There are far worse choices if you are looking for some dumb movie length anime entertainment.