In modern day, a condemned prisoner Marcus Wright is convinced to donate his body to science--specifically to Cyberdyne. Then he wakes up in a future where everything has gotten all blowy-uppy. He meets teenager Kyle Reese, and eventually John Conner--the prophesied savior, but no the commander, of the resistance. Surprise surprise, Marcus turns out to be the protoytpe flesh-and-steel terminator, but doesn't actually know it (he thinks he's human). Then more things blow up, plot holes are ignored (why is John Conner surprised to find a machine who tries to protect him--isn't that what his entire childhood was about?), and Marcus Wright becomes a Christ figure. And there's no time travel, so I'm immediately turned off.
Maybe I'm being too harsh. The first TERMINATOR was a b-movie that was much, much better than a b-movie is supposed to be. TERMINATOR 2: JUDGEMENT DAY was a sequel that was much, much better than a sequel to a b-movie is supposed to be. TERMINATOR 3: RISE OF THE MACHINES is the third in an action movie series that is exactly as good as it should be. The series no longer rises above its ambitions, and is just a standard action franchise now (I'm ignoring the TV series because it's both more interesting and more frustrating than the movies, and kind of exists in its own world). So as the fourth installment of an average action sci-fi franchise, TERMINATOR SALVATION is probably just as good as I should expect. I just shouldn't expect the franchise to keep exceeding expectations.
And now I want to go an a little pointless rant about the logic of time travel in movies. In short, if you cannot draw a self-consistent space-time (Feynman) diagram with closed time-like loops, it is not a time travel story (examples of consistent time travel movies: TIMECRIMES, 12 MONKEYS, and with some comedic license BILL AND TED'S EXCELLENT ADVENTURE). Many more movies take a "branching universe" view of time travel--when you travel back in time you create a new branch and change everything in the future. However, these are not really time travel stories. More specifically, you can tell the exact same stories without using the concept of time travel--instead you can call it travel to an different possible world (or alternate universe, or whatever you want to call it) that happens to share a history with our universe up until a specific point in time.
There's nothing wrong with travel-to-different-possible-worlds-that-share-a-history-up-to-a-point stories other than:
- The unwieldy name
- The near-ubiquitous logical error that somehow what happens in the future of the alternate world somehow affects the the future of the original world.
I've had a friend argue that perhaps the act of travelling back in time creates a new branch and destroys the timeline of the original world. That just creates far more problems, like where did the time traveller come from if his world doesn't exist. At the very least, he shouldn't retain memories of events that have never and never will happen. His memories should immediately be replaced with memories from the new world. Basically, in order for a story to really be about time travel, both the past and the future have to be consistent.
To bring it back to the TERMINATOR franchise, the first movie was logically consistent (a bit of a mindbender, Kyle Reese being John Conner's father, but Feynman-diagrammable). It did not embrace my view of time travel logic--Reese mentions different possible futures--but it is till diagrammable. T2 is also kinda consistent--if you choose to believe that the attempts to keep Cyberdyne from inventing Terminators completely failed (and if you regard the closing monologue claiming "the future is unwritten" to be bullshit). T3 introduces the "fact" that Judgement Day was not stopped, only delayed. This becomes problematic unless you consider that we only have hearsay about the date of Judgement Day, and the reports might be wrong...by several years.... Okay, the franchise is definitely embracing a "branching worlds" take on time travel, but I could still diagram T3.
And so we get back to TERMINATOR SALVATION, and one of the main problems I had with it. The main plot point is that John must save Kyle Reese so that he can later send him back in time to be his father. But either this is a self-consistent, Feynman-diagrammable universe--in which case it's a forgone conclusion that Reese will survive; or it's a branching-worlds multi-universe--in which case it doesn't matter if Reese survives, because clearly he survives in at least one possible future and John sends him back in time from there. As a physicist, I wanted Kyle Reese to die so I could see if John would suddenly blink out of existence or something (however they'd try to handle that).
Okay, that was way more writing than that movie deserved. I'm done.