I love this movie: http://www.imdb.com/title/tt0390384/
I've watched it so many times I've lost track... which, oddly, fits neatly into the theme of the film itself. My friend Max Guernsey recently watched it and asked some questions that got me thinking about the film all over again. So, I thought to write a blog about it.
If you have not seen the film, please do not read this. In fact, please do not read this unless you've seen it at least twice. I would hate to rob you of a truly wonderful experience by spoiling it.
Shane Carruth says he did not really start out to make a film about time travel. He wanted to make a film about trust, the sacrifices we make (or refuse to make) for friendship, and the human desire to "get things right" in our lives. The device Abe and Aaron create is a vehicle (pun intended) through which the film explores these themes.
The plot is confounding, no doubt. Here is my take at untangling it:
Alert! Spoilers below...
Abe is the first one to realize what they have. He plans to prove this to himself and to Aaron by starting the box, sequestering himself in a hotel for a while, then entering the box to go back to just after he started it. Once he does this he finds Aaron, and together they watch the original act of Abe starting the box and leaving for the hotel. Aaron believes what he sees, but what he does not know is that Abe secretly created another box and turned it on earlier. It is still running, and will continue to run until/unless he decides to use it This is his "failsafe", which he can use if things go wrong; he can go back before he decided to tell Aaron about the discovery, and stop himself from doing so if need be. He is not sure he'll need it, but there are so many unknowns that Abe, the good engineer, takes this precaution.
We do not see Aaron finding Abe's box, but he does as we find out later (in a sense). He moves it to another location and replaces it with a box that he activates after Abe's original experiment. Thus, he will be able to go back before this all began, but Abe will not be able to. Aaron does not want Abe to be able to thwart him in what he intends to do. Note that Abe's motivations are very different from Aaron's.
Abe is dating Rachel Granger. Their efforts are funded by Rachel's father, Thomas Granger. At some point, in a future we do not see, Granger finds a box running (we do not know which one, or how) and uses it to come back for reasons of his own. He may, in fact, believe he will go back to the original failsafe point and take control of the technology from the boys. He makes the mistake of exiting the box early, however (as Aaron did when they first traveled, only even moreso) and this damages him severely.
Abe is very disturbed by this, and also by a tragic event at a party involving Rachel's ex-boyfriend, and finally decides to use the failsafe to go back and prevent the entire series of events. He does not know that his failsafe is not the original, but the one Aaron replaced it with. So, when he goes back he actually does not go all the way. The Aaron that Abe now encounters is already a time-traveler. The original Aaron? Drugged and in the attic.
Aaron tells Abe the truth... he has been looping back over the events again and again, taking a machine with him (folded up) in the failsafe and, exiting, starting the new machine up so he can go back again. He is trying to make the "perfect day" where the tragedy at the party, and the tragedy with Granger, never take place. Now Aaron takes two folded-up machines back with him...
We do not know (cannot know) how many loops they go through (and how many drugged Abe/Aaron versions are in the attic) before he succeeds. But he does. They decide to do one more loop in which they do not set a failsafe again, and start a new time line that cannot loop. Aaron decides to go off continent so he can never encounter another version of himself, and begins to build the room-sized machine. What he intends is unclear. Abe stays in the states and will prevent them from ever discovering time travel in the first place. Their friendship is over.
We also are travelers, of course, as the film was made long ago but we can restart it and watch it whenever we wish. We do do, of course, because we want to change our experience of the film by coming to understand it better until, I suppose, we create the "perfect run" of the film.
I'm sure I am missing things here. I like that. The whole thing just makes me smile.