This is an endlessly hypnotic and entertaining movie. Not in the usual, audience friendly way, but in how it demands from you to be alert the whole time. Really, you can't do as much as blink during this film without missing some important development. I don't agree that this is a film where is best to not pay attention to the plot because it's so dense. I mean, that's all they talk about, and it's not like the film leaves that unresolved. The thing is that PTA is basically continuing what I've always felt was the most distinctive feature in The Master, which is the "nuts and bolts" approach to the narrative and editing.
I saw IV and tried my best, but by the end it was clear there were things I just didn't understand, characters I didn't fully grasp where they came from and why they were there, and a few details that when I re watched the next day turned out to be important. And yes, of course on second viewing the whole who dunnit plot was crystal clear, and the melancholic atmosphere more resonant. I commented about The Master that the film goes from scene to scene with such a fast tempo and dealing only with the most essential information (visual, narrative, performance wise) that audiences cannot keep up with it, give up and then accuse the film of being slow. With IV the same is happening (slow is now accompanied by incoherent), even though there are no loose ends in this film, beyond the unimportant details of how the Golden Fang works or it's actual reach in this world. The thing is that just like in The Master, this film is not waiting for anyone.
Take the first scene, where the plot is set. It just starts. And characters waste no time explaining anything to us more than once. If you don't follow the intricacies of this setup only in this one scene alone, you're already lost before the 10 minute mark. The film keeps this pace all through it. Essential information (again plot-wise, character, visual, narrative-wise) is given like a clock, and it's a testament to PTA's brilliance that within this merciless discipline he manages to create a languid, relaxed and at the same time funny, paranoid and melancholic mood. The Master's story is like an Aesop's fable compared to the complexity of IV's plot, with many places, names, references, thrown in scene by scene. Sure, the film aims to portrait confusion and the feeling of being lost in a haze, but it's not actually abandoning it's plot and it's main character's essentials (it has been already been brilliantly pointed out here that Doc's arc has to do with recovering SOMETHING in light of his loss of Shasta, who's definitely gone after her first scene, and that something materializes in helping Coy to return home).
I'm very excited by what PTA is doing with narrative cinema. He might just be the only filmmaker within this trend to be actually exploring new ground and finding new ways to do strictly narrative films. I know he's an Apichatpong fan, but unlike him and many other auteurs who are basically on the other end of the cinema spectrum, he feels no need to extend takes endlessly or fill minutes with silence as a way to contemplation. He does the opposite, and I think he's on to something really special.