This was an interesting 80s anime - demons erupt in central Tokyo (of course), and infest it with evil. If mankind doesn't soon find a savior to battle the demon ninja who is bargaining with the devils, the whole globe will be given over to the demons. Uh oh.
Luckily our hero proves to be just such a savior, and along with his female companion and various sidekicks he does battle with demon after demon, fighting his way to the main bad guy.
The animation is superb, the story is interesting, and the whole thing piqued my interest. Recommended.