Ultimate Avengers 2: Rise of the Panther (PG-13)
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Caution: potential spoilers.
It begins in the isolated African country of Wakanda. Prince T'Challa has just returned from his studies in the outside world, where his father, King T'Chaka, had sent him against the advice of the council of Elders. The king is also a hero known as the Black Panther, and he fights a Nazi called Herr Kleiser. So at first you might think the movie is set in the past, like the first Ultimate Avengers movie starts out, but it's not. Kleiser is actually a shapeshifting Chitauri, whom Captain America had actually fought during WWII, and apparently killed at least a couple of times. But he's survived into the present, and now he kills the Black Panther, as T'Challa watches. So the prince becomes the new king of Wakanda, and assumes the mantle of the Black Panther. He goes to S.H.I.E.L.D. to ask Captain America for advice on fighting him, but there's nothing he can tell him except that it seems to be impossible to kill him. Fury and the Avengers offer their help, but because of Wakanda's isolationist policy, T'Challa must refuse.
Of course, Cap has a grudge of his own to settle with Kleiser, compounded by his difficulty in dealing with all the changes he's had to face since waking up in what is, to him, the future. And also, Fury wants to figure out what the Chitauri are up to in Wakanda. So the Avengers go there anyway... and are found and defeated by the warriors of Wakanda, and told to leave. Meanwhile, Bruce Banner is locked away in a nearly indestructible room, watched over by a doctor who has a grudge against him, and forced to repeatedly watch a video of the destruction wrought by the Hulk in the previous movie. Bruce wants to see Betty Ross, but she doesn't seem to have much interest in seeing him, or much sympathy for him. She does see him once, and tells him that nobody trusts him anymore. Thor, meanwhile, is off on his own somewhere, when he has a vision of the deaths of the Avengers. He asks his father Odin about it, and Odin orders Thor not to intervene in the affairs of humanity, since they've turned their backs on the gods. Thor refuses, however, and goes to help his comrades.
It turns out the Chitauri want to obtain a meteorite that crashed in Wakanda long ago, which contains a great deal of unrefined vibranium. The Wakandans have forged it into weapons that can be used against the Chitauri, which comes in handy when the aliens launch a full-scale War of the Worlds-style invasion against the Earth. However, it's still not enough to stop them. Meanwhile, after watching that tape so many times, Bruce finally spots something useful, information that can help S.H.I.E.L.D. and the Avengers fight against the Chitauri, information which he shares with Betty. Of course, while the Chitauri are attacking the whole world, they do have several primary targets, not just Wakanda. They also attack S.H.I.E.L.D. headquarters, and Bruce's cell. But even they can't penetrate it to kill him (which they want to do because the Hulk is a threat to them). So they try to get the doctor to open it, but only Fury has the access code, so they're going to kill the guy... but then he says he can kill Bruce, with a lethal dose of the sedative gas he uses to keep Bruce from getting angry enough to turn into the Hulk.
Let's see, what else happened? Oh, Cap encountered Black Panther with an apparently near-dead Chitauri, and took them both onto their plane, but it turned out to be a trap, and it resulted in the Wasp sustaining injuries that put her in a coma. Before this, she had been arguing with her husband, Giant Man, because of his ego and generally bad attitude. And now he wanted to become the man she wanted him to be, but it seemed a bit late, and he was really mad at Cap for his mistake hurting his wife like this. Anyway... well, lots of characters seemed close to death at various points in the movie, and it always ended up causing other characters to reveal their true feelings about them. And um... I don't really want to say whether everyone survived, but you might be surprised.
I suppose I'm forgetting things and not saying all this in the proper order exactly. But of course the Chitauri are ultimately defeated. At least for now. And um... well, it was a pretty good movie I thought, maybe slightly better than the first one. I do wish there'd be more movies in the series....