This is sorta gonna be difficult. There's a tremendous limit on what I can say.
I know the first thing to say which is DON'T BE SPOILED! Be like me and see it without any preconceived notions of what happens. Don't let anyone ruin that experience for you.
This film truly is the culmination of everything that has happened for the past decade since we first met Iron Man. There are moments that are callbacks to so many of those films. And that is both the film's strength and it's weakness. If... IF... you have seen pretty much everything in the Marvel Cinematic Universe, you will probably love this film. But, if you missed Spider Man or Guardians of the Galaxy or Thor or Black Panther or Dr. Strange or Age of Ultron or Civil War, these characters and their motivations may frustrate you. The movie, while being 2 1/2 hours long, does not have time to set up who the characters are, what their relationships are, what powers they possess, and (most importantly) their motivations. You must walk into the theater knowing all of that stuff already. Black Panther was not that way... Dr. Strange was not that way... even the latest Thor film was accessible if you only had a passing knowledge of the MCU. Not this film.
So, consider the rest of this review to be for those die-hard MCU fans out there. This isn't a movie designed to draw in the unfamiliar. This is a reward to all of us who have been waiting a long, long time to see all of it come together in one grand cinematic moment. There have been 18 movies leading to this point and every single one of them has played a role in getting us here. If all those films were appetizers or entrees this is, at long last, our dessert.
And what a dessert it is! Great action scenes, some of which are intimate and some incredibly expansive. This is said to be one of the most expensive films ever made, a budget of more than $300 million, and you can see every penny of it on the screen. The effects and the sets are jaw-dropping.
The story is intricate and the dozens of superheros in it play individual roles in moving the plot along. But, moreso than anyone else, the star of the film is the bad guy, Thanos, as well as his main henchmen known as the Black Order. They are imposing, ruthless, and deadly. From the very start of the film it is clear that our heroes, even banded together, have very little chance of victory. Josh Brolin, who voices Thanos and did motion capture work on the character, is fabulous. It is one of the more emotional and powerful motion-capture performances ever... maybe not quite what Andy Serkis has done with Gollum or Caesar, but darn close. The movie does an ok job of explaining his motivations, but I still wish we had gotten to know more about Thanos' back story and what led him to the path he is now upon.
The film is tonally strange at times. Like everything in the MCU, it is peppered with a lot of funny moments, some of them truly hysterical and memorable. But, in the final third the movie gets extremely dark and almost depressing. There are a number of serious gut punches (you know there would be) and there were repeated gasps from the audience. A couple times you heard the theater scream "no!!" The reality is that some folks will leave this film angry at how things turned out.
I'm not sure there is much more I need or want to say. Some of the Marvel fans I saw it with were grumbling a bit as they walked out. Others were cheering and had a real bounce in their step. I guess I fall somewhere in between... I really enjoyed the ride, but have some problems with where it took me in the end. Still, this is a must-see if, like me, you have seen all that came before. And, as I said at the start, see it as soon as you can so you will not be spoiled.
-Jason "I look forward to talking spoilers with all of y'all starting in a few days" Evans