It's Hayao Miyazake again. The story is about Porco, a self-employed fighter pilot who also happens to be a pig, in the Mediterranean in the 1930s. He used to be Marco, a human pilot. He and his best friend joined the Italian air force to become fighter pilots in World War I, but his best friend, and most of his squadron, was killed in combat. This is the spell that turned Marco into Porco. (All of the dates and countries are rough analogues; the story is not intended to be historical, but merely rhyme with history.)
Porco is a bounty hunter who hunts pirates, of which there is no shortage. He is challenged by a man the pirate gangs hired to take him out. Honor compels him to the fight. Along the way, he is helped by Fio, a young woman who turns out to be a budding young aviation engineer, and she gets involved in the duel. In part for his own honor, and in part to save her, he stakes everything on one dogfight.
For her part, designing the best amphibian fighter plane in the world is Fio's challenge, and also finding the answer to whether or not Porco can be saved from his spell.
It is worth watching for the imagery, the music, and the story. You will not be enlightened, but who says every movie must make you rethink your life?
One caveat: In an odd juxtaposition, the early part of the movie is much more for children than the latter part. When I first saw the early part, I thought, oh, that's cute. After seeing this movie several times, I just put up with the first part in order to get to the story I'm interested in. It's a good time to make popcorn.
A second caveat: There is a point in the movie where a good friend is asking Porco not to get into this fight. In the translation, Porco replies: "A pig's gotta fly." However, the actual Japanese is: 飛ばない豚はただの豚だ. "A pig who doesn't fly is just a pig."
I understand the difficulties of translating for a movie. You have to get the meaning across, but also stick to the time allowed the scene. However, the Japanese reply carries a deeper meaning in the context of Porco's transformation from human to pig, and his insistence on personal honor when his friends have died in a lost battle and things like national honor and pride have been demolished.
UPDATE: Normally, I suppose, you watch the movie and then review it, but I had seen it maybe half a dozen times, maybe more, so I didn't bother to watch it again before posting this. I didn't intend to watch it again today, but after posting I couldn't get it out of my mind, and I had a bottle of Italian wine in the cupboard ... The children's part is shorter than I had remembered, and the whole story does depend on personal honor. The topic is brought up at several points in the story. Also, during this time Italy is turning to fascism, which is one reason why Porco doesn't return to the air force, and why he can no longer rely on national pride or honor, but only the honor of one man, er, pig, standing against the world. (Really, one man and one woman.)
I watch it in Japanese, so maybe I'm not the best one to offer advice here. In considering a non-Japanese-speaking audience, I tried watching it dubbed in English, but Michael Keaton's voice was jarring. He may be Batman, but Porco? I don't think so. I recommend it in Japanese with English subtitles if you don't mind subtitles. If you do mind subtitles, well, Michael Keaton's not terrible.
If you are the type who matches movies with drinks, allow me to recommend the Gabbiano Chianti Classico for a richer taste, or the Placido Chianti for a smoother taste, for this movie.