|Jake Gyllenhaal is|
Captain Colter Stevens
Gyllenhaal then catches a glimpse of himself on the train window, and is suddenly even more confused. He dashes to the restroom, and discovers that his face isn't as he remembers. He returns to his seat, and after a brief conversation, the train explodes suddenly. Gyllenhaal then awakens inside a dark chamber, strapped into his seat by a military style seat belt. He is a bit gaunt, paler, and seems in distress. A voice calls for him, saying that "this is Beleaguered Castle," and issues him commands. Gyllenhaal is still confused, and doesn't recognized the person on the screen, a Captain Goodwin, played by Farmiga. She then begins a cryptic sequence, involving cards and a woman, and suddenly Gyllenhaal remembers who Farmiga is, but is still confused about his whereabouts.
Eventually we discover, along with Gyllenhaal, that he is part of an experiment named Source Code, run by a scientist played by Jeffrey Wright named Dr. Rutledge. In essence, Source Code enables them to tap into the brain of a recently deceased person and play back the last 8 minutes of his life. However, more than simply a recorded remembrance of the dead person's last minutes of life, it allows the Gyllenhaal to move about and actually change events. Rutledge speaks of quantum reality, in essence implying that a new reality matrix simulation is being recreated with Gyllenhaal as the protagonist.
Gyllenhaal also discovers that he has been mortally wounded in Afghanistan, and that the world thinks he died while bravely saving his comrades. He surmises that he is basically plugged into the machine, living under while life-support. The reason why he is being sent back to the train is explained to him: there has been a terrorist attack on the Chicago bound commuter train, and the same person that committed the attack has threatened to explode a dirty bomb in Chicago and endanger millions of lives. Rutledge grudgingly agrees to end Gyllenhaal's life if he can discover the identity of the terrorist.
The end is reasonably satisfying, and ties in nicely with the quantum reality idea proposed by Rutledge. The movie has been directed by Duncan Jones, who also helmed the excellent movie Moon, starring Sam Rockwell. Source Code is in essence an action fantasy with some romance between Gyllenhaal and Monaghan. Farmiga is excellent as usual as the military handler with a conscience, and Wright brings surprising depth to his brief appearances as Rutledge.
The special effects are serviceable, nothing over the top. Farmiga and Gyllenhaal do competent jobs of acting - Gyllenhaal is usually very good and so is Farmiga. Monaghan seems a bit underused, but then again, for a character that is forced to constantly relive the same 8 minutes, she doesn't have much room to grow. All in all, a worthy movie for a rental.