I've never been of the mentality that just because a movie is an action movie or special effects movie or meant to be some sort of visual spectacle, that it makes it okay for movies to be dumb, have horrible writing or really stupid plots. (Seriously, in GI Joe: RoC, the under water station was destroyed by rapidly sinking Ice. No one but me has a problem with that? I digress.)
That said, I really enjoyed Pacific Rim. The writing and dialogue were atrocious in some places, seriously horrendously bad and I laughed out loud at it. The thing was, I felt like in many places in the movie, I was kind of supposed to. The Movie never took itself too seriously, the dialogue, bad as it was in some places, never seemed forced or like it was intended to be profound. It felt to me like they knew it was cheesy, they played into it a bit and they showed a lot of Robots fighting Monsters.
That's the other thing, I feel like so many action movies that end up dumb with bad lines and what not, still don't do a great job at showing me the action, or the visual spectacle. And this movie not only understood it was cheesy and did okay with that aspect, they nailed the Giant Monsters V Giant Robots thing, seriously jaw dropping spectacle in a way that honestly felt too big even for the massive I-max screen.
So I'd recommend it to anyone who likes sci-fi, fun flick and as there were some big plot holes and horrible lines in some places, none of it was completely stupid, too serious or really all that bad, and the action sequences and breath taking scale of it makes everything else completely moot.
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I did have one major nitpick though. Why on earth would you not build more ranged weapons onto the Jaegers? What you can build giant effing robots with whip swords but you can put a big rail gun or machine gun on there? Make those things like mechs with shoulder mounted missles everywhere and lasers and the whole bit.
And the ranged weapons they did have, they never wanted to use them until after they had punched the monster a few times and got in close. Is there no targeting system on those things? I mean it's a giant freaking monster, you can't hit that from more than a half block away? Wouldn't it be smarter to weaken the things with the plasma guns or chest missles BEFORE they got in close enough to get their damn dirty paws all over the mech?