"Source Code" could easily have been released during the '70s, the era of high concept science fiction and paranoid thrillers. Director Duncan Jones manages to update those formulas, though, into a smart action movie that fits perfectly into 2011 America.

Colter Stevens (Jake Gyllenhaal) is a good, compassionate soldier. He does everything in his power to complete the mission while protecting the innocent.

But Colter's current mission is unique to say the least.
Colter wakes up on a commuter train in the body of another man. He doesn't know how he got there, who the man is, or what he is supposed to do. A woman named Christina (Michelle Monaghan) begins talking with him as if they are old friends.

Eight minutes go by as we, and Colter, notice fine details and minute actions of the other train passengers - before the entire train car explodes.

Colter then wakes up in his own body, but now he is in a small capsule and communicating via video screens with officer Colleen Goodwin (Vera Farmiga). Colleen explains that the train explosion happened earlier that morning. It was a terrorist attack.

Colter's mission is to relive the memories of a passenger killed in the attack then report anything that might help catch the terrorists. The mission is especially urgent because there is another bomb set to explode in downtown Chicago within hours, so Colter must retrieve helpful intelligence in time for the Defense Department to stop the second attack.

We have a literally ticking bomb elevating the suspense, but the nature of Colter's mission raises a number of big questions. How is this possible? Where is Colter's body and what happens after the mission? Colter also struggles mightily with the fact that he can gather information but can't stop the attack on the train.

Colleen is Colter's handler, but the operation is driven by Dr. Rutledge (Jeffrey Wright), who couldn't care less about philosophy or metaphysics. He invented the system and just wants it to succeed, for his own gain as much as the safety of the U.S.

"Source Code" solidifies Jones' reputation as a rising star of international cinema. His debut feature, "Moon," didn't play widely in theatres but earned strong critical praise and a devoted fan following.

Jones is among the best young directors when it comes to building strong characters into science fiction scenarios, but he deserves particular credit for simply making "Source Code" intelligible. In less competent hands, this concept easily could have spun out of control and become too confusing for us to care.

Instead, Jones shows an impressive ability to blend in exposition without bogging down the plot and an awareness of when to break from the action to focus squarely on how this odd state of being affects Colter.

Anyone who can almost seamlessly integrate discussions of alternate realities and wartime ethics into a riveting thriller with a romantic subplot clearly has some game.
Gyllenhaal is back where he belongs, playing a grown-up everyman. His turn as an orphan prince in "Prince of Persia" was a misstep all around, and his cocky sex addict role in "Love and Other Drugs" wasn't much better.

Here, though, he excels as an average guy placed in a nearly impossible predicament, and this movie proves what "Persia" didn't - that Gyllenhaal can carry an action movie.

As Gyllenhaal's love interest, Monaghan doesn't get to do much, but she seems to get more charming and skilled with each role. Farmiga, on the other hand, earns a big assist for helping Gyllenhaal create the emotional foundation of the movie. And Wright is great as always, this time getting to play a geeky heavy.

The only exception to Jones' excellent execution is one troublesome existential point which emerges during the ending. But by the time we get there, the movie has been too fun and frenetic to nitpick.

Jeff Marker is a media studies professor at Gainesville State College.