How do you even review a film like this? I mean, for one, it can't possibly exist without what came before yet, in an alternate way, neither could the prior film exist without this end point (or ... end game ... ha, see what I did there?)
One of the biggest events in cinema history, in which 18 prior films come smashing together (unless you're Ant-Man and Hawkeye, who only get one mention in this movie. Real tears were shed folks. How can you leave out my two favorite characters?????) into what SHOULD be an epic mess but is, in reality, a masterfully written, almost perfectly edited behemoth that manages to tell a simple A-B-C story (stop giant purple dude from getting shiny things) all while converging many different genres of films and drastically different characters into one cohesive unit WHILE ON TOP OF THAT fleshing out a completely new character who MUST command the screen to make the whole damn universe work.
Those who think the MCU is commercial garbage truly don't understand or appreciate the true artistry it took to bring what is essentially an epic 19 part story to theaters this way, culminating in Part 1 of a 2 part finale that could go down as one of the most complete, wide-ranging, funniest, saddest, emotional endings ever. Ambitious, epic while also staying true to its roots, Avengers: Infinity War is an achievement to be remembered in the halls of history.
Now, the spectacle and wow factor is on full display and that can shield some of the errors or issues at hand (just because the film is edited well doesn't mean it doesn't mean it is batting 1.000 when there is just way too much going on) but, like most MCU films, you have compelling characters, approaching impossible odds, and staying true to themselves. Unlike Age of Ultron, where it seemed like Joss Whedon forgot the characters had evolved, Infinity War somehow, and I don't know how they did it, kept every single character true to their nature ... not one character betrays themselves out of plot convenience. This is another example of the film's unrecognized genius (and yes, I count Star Lord in this argument ... what he did was bone fucking stupid ... but it was completely in character).
Anyway, like I said, it is hard to review this film because it is such an experience ... one dictated by how divested you are in the universe. The simple "stop-Thanos" story is compelling enough even if you have no idea who anyone is, especially since this is Thanos' first actual role (he had about two scenes of dialogue and quick end-credit appearances in three previous films) and Josh Brolin brings three dimensions to him. Much like Kill Monger before him, there are times when you realize maybe the LOGIC isn't that bad ... it is just the execution.
In a year of really excellent Marvel films, Avengers might not match the soul of Black Panther, but it certainly captures the emotion ... the ending, even if you are cynical and know it all means nothing, is so off putting and uncomfortable that when Star Lord says "did we just lose", you kind feel like you did.
Great film ... endlessly re-watchable ... and you ALWAYS get a fun moment out of unexpected couplings (anyone who thought Bucky Barnes and Rocket Raccoon would share a scene together or that Nebula and Tony Stark would be forced to become partners by films' end was a genius ... I don't think anyone thought of that). Seriously ... I could watch it again right now.