The theme of Strings is that we are all bound to one another.
The story itself is a hero saga, with our hero the young price setting forth to avenge his father that he wrongly believes to have been slain by their historical enemies. Of course there is an evil uncle who is furthering this for his own ends, being control of the kingdom, but that is about as trite as the story gets.
From here, however, we begin to learn that father was not always a great man, and that these rebels are really the victims of war crimes. After much travel and travails, our hero ends up back in the city without the evil uncle knowing. He learns see from his heart (or use his ki, if you think that way) and escapes from the prison just in time to hold his sister while she dies.
The story is well told, and well worth the watching if you don't mind the marionettes.
A lot of great voices in this but I got bored. I don't know why I didn't enjoy it near as much as Team America, but maybe it was the subject and not the actual movie. I just didn't enjoy it and didn't get past the 10 minute mark.