I wouldn't really call it better, they operate on different scales. Primer is much less bombastic and doggedly grounded to reality, which is really an anomaly in sci-fi media. Failure of the protagonists in Primer does not mean a World War 3 will happen or the planet will be destroyed, the biggest stake in the movie is one of the characters getting shot at their birthday party by an ex.
Personally I find this much more refreshing than the usual the-world-will-collapse scenarios. It's easily one of my favorite films, just because of how different it is than it's ilk, I've yet to find something like it again.
One of the main characters (Aaron) fled the country and is seen with the people in the warehouse presumably making a bigger version of the machine for unknown reasons.
The other one (Abe) stayed back and kept on trying to travel to the past and messing around with the machine so that his (and Aaron's) past selves will eventually give up assuming that the machine doesn't work. But this seems to have been thwarted by one of the future-Aaron's as he has sent a recording detailing the whole scenario to some unknown recipient (this recording serves as the narration of the movie).
> OK. So they're planning an invasion of the past?
No, you can only go back to the point where you start the time machine. Secondly, its Aaron, so its probably his private corporation running the new machine. Aaron is the one who is manipulating the stock market and in it for the profit.
Its the "success" story for Aaron, he rebuilds a bigger time machine, but with the power of a corporation / large money backing him now (probably funded from repeatedly winning in the stock market). Aaron cannot stop the original experiment or otherwise travel to the past, but he can make money in the future.
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There are roughly 3 machines you need to be aware of.
1. Machine #1 is what the movie is mostly about.
2. Partway through the movie, Machine#2 (failsafe) is revealed. The main character turned on the failsafe simultaneously with Machine #1, so if the time-travel got too confusing, he could always go back to the beginning and turn off Machine #1, cancelling the entire experiment.
3. The other main character, reset Machine #2. Instead of sending you back to the beginning, it now sends you to Day2 or so, preventing the change of the early days.
4. The conclusion, where Machine #3 is revealed. There was no leadup to machine#3, its just a bit of closure for the greedy Aaron.
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The movie goes off the rails and really stops making sense. I've put a lot of effort into trying to understand what they were going for... and ultimately came to the conclusion that Stein;s Gate is just a better thought out time travel plot.
I give Primer credit for being a relatively consistent time-travel movie with more thought put into it than the average time-travel timeline. But the ending is still in the "audience's hands", and still leaves ambiguity for the audience to figure out on their own.
A lot of actions in the middle of the movie don't seem to have any relevance to other events. The father (Thomas Granger) randomly coming in through the time machine but unconscious for example. While it is clear that Thomas Granger is from "some future timeline", such an interpretation naturally conflicts with the Primer theory thus far (which has no "multiple timeline", everything should be consistent)
There is also an Aaron clone running around, but it isn't really clear from what time the time-clone is from.
I don't think their intentions are clear. It's more that a powerful organisation or government now has control of it and is planning something large scale, beyond what we'd seen in the film before.
It isn't explained, which is my main fault with Primer. Primer leads you in with a crystal clear beginning that makes sense, but goes off the rails by the 2nd half.
A lot of people are tricked by the crystal clear beginning and assume that the end makes sense, but the movie goes into ambiguous mode about half-way through. Its audience interpretation, as opposed to a singular answer. (Contrast with something like Inception, which doesn't really have more than one interpretation).
Some people like ambiguous movies. I don't, which is why I kind of prefer Stein's Gate, where all actions are clear.
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Either way, its clear that the powerful organization is Aaron's goons. Aaron was the guy who played the stock market with the time machine, so its obvious that Aaron used the time-machine for ill-gotten gains at that point... and is using the money to fund a bigger time machine.
Personally I find this much more refreshing than the usual the-world-will-collapse scenarios. It's easily one of my favorite films, just because of how different it is than it's ilk, I've yet to find something like it again.