The movie continues the progression of the Infinity War story, which, since it's been announced as the next movie, I'm not treating as a spoiler, but, more importantly, it sets the stage for the next Captain America movie, which I'm also not treating as a spoiler since it's also been announced.
Beyond that, there's not much I can talk about without spoilers, but I will say this (because it was in the trailers and virtually everyone must have seen pictures by now):
The fight between Iron Man and the Hulk was amazing. Iron Man's Hulk-buster armor is awe inspiring.
Oh, and I really, really hope that this Avengers is also setting up for another solo Hulk movie. Now that we have Mark Ruffalo, it's about time.
Which brings us to the actors. I don't know what there is that can be said about the returnees that hasn't already been said. There's no weak link. Not even Jeremy Renner as Hawkeye, who has emerged as a more central figure in the team dynamic. It's good.
So let's talk about the newcomers:
Aaron Taylor-Johnson as Quicksilver -- He was adequate. It was more that there wasn't enough screen time for him to get a feel for him as a character than it was about the acting. The character in the movie is not the same as the Quicksilver from the comic (who is, more than anything else, haughty), so there was nothing to draw from. I think his signature line really worked for him, though.
Elizabeth Olsen as the Scarlet Witch -- She was suitably spooky in her movements and, although there is a bit more development with her, it still wasn't enough for me to get a handle on her as a character. Again, she doesn't remind me at all of the character from the comics.
Speaking of comparisons to the comics...
I mentioned in one of my earlier Marvel Studios reviews the need to be okay with the divergence of the movie universe from the comic universe. I get that, and I'm okay with it. I don't have a problem with the link to Magneto being removed from the brother/sister duo (though I know that there has been a lot of pissing and moaning about it in some circles). I don't have a problem with the changes to the origins of Ultron and... well, I'll leave him nameless, just in case. The movie universe is not the same. That's fine. The lack of relation to the comics with the case of Quicksilver and Scarlet Witch just leaves me without a comparison to make. They were fine. I just need to see more development before I can form an opinion.
James Spader as the voice of Ultron -- Since his bizarre run in The Office, I've found his new quirkiness fascinating. He used it well as Ultron, playing off of the personality of Tony Stark perfectly. He was great.
Age of Ultron is a great addition to the ongoing Marvel movie story line. In many ways, it is a standalone movie, sort of like an episode of a TV show, something Joss Whedon does well. It has a concise story arc that begins and finishes in this movie, and you don't really need to have seen any of the other Marvel movies to understand what's going on. Having the background makes it a richer, more full experience, but you don't need to have seen them. On the other side of that, you can see the various plot threads the pass through this movie come into it and go back out again (especially the stuff with the Infinity Gems), and that takes more than a small amount of skill to weave those things through without them being a distraction to the main story.
I think I had one small complaint with the movie, but I don't remember what that was, now, so it can't have been that big a deal. It's probably not quite as fun as the first one, but that's about it. I would probably call this a 4.5, but I'll give it the full 5 just for bringing in some of the side characters, especially The Falcon.
