Action movies tend to play a game of chicken with their audience in the second act: they want us to think that the hero could really die, but we know that the hero isn't going to die in the middle of the movie. Generally the audience blinks first and just buys into the obvious lie that the danger the hero is facing could be fatal, even though we know that the worst outcome is probably a setback or a dead sidekick. We suspend our disbelief because if we don't give the filmmakers the right of way then there's a head-on collision and no one goes home happy.
Edge of Tomorrow doesn't play this game and it is much better for it. The premise of Edge of Tomorrow is that Tom Cruise is a PR flack for the army who gets drafted into a war against invading aliens. After he gets accidentally dosed with magic alien goop Cruise discovers that he is stuck in a time loop and that every time he dies on the battlefield he instantly wakes up back on the army base on the day before the attack. No matter what happens in the battle he seems to die, but no matter how many times he dies he keeps resetting to before the battle. He begins the hard process of trying to figure out how to win the unwinnable fight by trying to change every variable he can, even though it means he gets exploded over and over again. (Well, exploded and also crushed; he gets swatted by alien tentacles as much as he gets bombed.)
Because Cruise is never really in danger of dying – or rather, is constantly dying in a way that doesn't represent a threat to his survival – the movie abandons the idea that we have to pretend that he is in danger when we know he's going to be around till the end. Instead, the movie becomes a puzzlebox. What is it that he needs to do to win? What is he missing? What other options are there that we aren't seeing? Instead of having to treat the action as being more serious than it really is, it can reduce the repeated battle scenes to sick jokes and then keep the suspense up by challenging us in a more intelligent way.
This was a movie where I was glad to give the right of way. Yes, parts of it strain credulity – I did, after all, just use the phrase “dosed with magic alien goop”; the time travel part of the story is probably better left unexamined – but there's so much good stuff that there's no point in niggling over those things. If you see enough action movies they all start to blend together, with the tentacles of one CGI alien blending in with the tentacles of another one. How funny is it that the one movie that stands out is the one that admits that every battle scene is the same?