Source Code begins with a great hook for a story, and wisely remembers that a hook is only that: a way in, not the story itself. It opens with a man (Jake Gyllenhaal) on a train headed into Chicago, with no idea how he arrived there. A woman (Michelle Monaghan) he does not know is talking to him in a familiar way, and calling him by a name he’s never heard before. He knows his name is Colter Stevens, U.S. Army — so why is the face in the mirror and the name on his driver’s license all wrong? And then the train explodes from a bomb hidden in it somewhere, and Colter is thrown back into his “real” body, strapped into a seat in a kind of armored pod.
It’s a military project, we learn. The eight minutes Colter spent on the train in the body of another man is a sort of a simulation — a kind of peek into an alternate dimension, one constructed from the remnants of the mind of the man Colter is being projected into. The woman, Christina, is the would-be girlfriend of the dead man. The “source code”, as they call this pocket universe, has been created so that Colter might go into it — as many times as required — and find out who set the bomb. There’s only one problem: Colter has no idea how he got into this situation in the first place, and doesn’t believe for a second that the people giving him orders through the little TV screen over his chair have any legitimacy.
There are other limitations. The girl across from him on the train always dies in the simulation, just as she died in real life. Saving her in the “source code”, as they call this simulation, does not change anything in the real world. But what he does may be able to save others in the real world,as the people who planted the first bomb are apparently readying another, far more fatal one — and the only clues as to their identities are jiggling around somewhere in those eight minutes of experience. And then come hints that the mission is not what it appears to be, that the source code is not what anyone really says it is, and that Colter is not what he thinks he is, either.
Source Code was directed by Duncan Jones, the same man who gave us Moon, easily the best English-language SF film since Primer. In Moon he started with a situation that could have been mined merely for its plotting and dug under its skin to gave us a deeply human story. The same goes here: Source Code begins with its Philip K. Dick-ian gimmick and becomes instead about Colter’s obsessive need to make the wrong things right, to go back into the maw of futility and fix what is theoretically broken forever, and to make that his last heroic act. (Which, if you think about it, is rather more Dick-ian than the premise we start with is.) The more he learns about his situation — and about what his captors plan to do with him — the more he tunnels back into the source code, both to find answers and to grow that much closer to the girl who has become the one spot of brightness in the dark.
Most of the way SF is foisted on a mainstream audience is by way of mixing it with another genre, or by hearkening back to a previous story regardless of genre. The obvious predecessor template for Source Code is Groundhog Day, wherein Bill Murray had to replay the same day of his life perpetually until he understood how to live it properly. That movie came on as an unassuming little comedy, and in retrospect it stands alongside films like The Truman Show for being both accessibly mainstream and profound. Another possible point of reference is old-school interactive fiction games a la Infocom’s A Mind Forever Voyaging. That story featured a supercomputer created to simulate the future from a first-person perspective — except that you were playing the computer, and had to navigate not only the complexities of the simulated world you were being projected into but the politics and machinations of the people running your programs.
Finally, I thought of Johnny Got His Gun, wherein a horribly crippled war veteran, believed to be brain-dead, tries to come to terms with the extent of his injuries and find a way to communicate to the outside world. (I was also reminded of that scene in THX 1138 where unseen technicians speaking in bored voices screw around with poor THX’s nervous system.) My mere mentioning of that film may well be a spoiler of sorts, although the way Source Code implements it is actually just a stepping stone to a much larger possibility that the film uses as its coda.
What makes Source Code work is not that it has a really nifty conceit or an airtight internal logic, although by the time we get to the end of the movie its logic has been tested and found sound enough to get us across the road. The film works because it starts on an intellectual level common to most brainy SF — “Gee, neat idea!” — and then moves from there to the emotional level common to all great movies — “Wow, what a story!” It’s also proof, once again, that a modest film need not be not a minor one, and that you can accomplish as much in one movie as you could with the catering budgets of some others.