Director Duncan Jones is back with his sophomore effort “Source Code,” a sci-fi action thriller set on a doomed commuter train headed toward Chicago. Starring in the film is Michelle Monaghan, a former Columbia student, who decided to pursue acting during her senior year.  Since then, she’s appeared in a number of films, including “Due Date” and “Kiss Kiss Bang Bang.” Now she’s appearing opposite actor Jake Gyllenhall in a film that finds her returning to her Chicago roots.

The Chronicle had a chance sit down with Monaghan to discuss “Source Code,” what it was like returning to Chicago and how she uses her Columbia education in her acting career.

Director Duncan Jones is back with his sophomore effort “Source Code,” a sci-fi action thriller set on a doomed commuter train headed toward Chicago. Starring in the film is Michelle Monaghan, a former Columbia student, who decided to pursue acting during her senior year.  Since then, she’s appeared in a number of films, including “Due Date” and “Kiss Kiss Bang Bang.” Now she’s appearing opposite actor Jake Gyllenhall in a film that finds her returning to her Chicago roots. The Chronicle had a chance sit down with Monaghan to discuss “Source Code,” what it was like returning to Chicago and how she uses her Columbia education in her acting career.

The Chronicle: I’m willing to bet most Columbia students have no idea you were a student here at one point. What was your experience like?

Michelle Monaghan: I loved my time there! I worked a lot during the day, so I took a lot of early classes and evening classes—you know, those three-hour 6:30 to 9:20 [p.m. classes].

The Chronicle: You were a journalism major while in college. Has any of that helped shape your acting career?

MM: Totally. And this is so crazy because I put myself through school. That’s a lot of money, and I remember thinking to myself, “Oh, my God, I can’t believe I just spent this much money on something I’m not going to do.” And then, as I was beginning my career—I think it was my role in “North Country”—I was writing about my character and I realized I was doing the who, what, when, where, why and how. All of a sudden, I saw it on paper and I grinned from ear-to-ear and thought, “Oh, my God, it wasn’t a waste!” and immediately felt like I had got[ten] my money’s worth.

The Chronicle: Did you do something similar for “Source Code”?

MM: I said to [Jones], “There’s not a lot on the page for her, clearly. Let’s create a back story for her.” So I went about creating a back story for the character.  And I thought, “This is a chick that is in a job she really hates. She takes the 8:20 a.m. train in from DeKalb to Chicago every day. She sits there and she’s miserable and she doesn’t live her life to the fullest.” I think sometimes it’s easier to talk to strangers than it is to be honest with yourself, so she just sits across from this guy and starts shooting the s*** with him one day, and he gives her a fresh perspective. I had to have all of that in my head.

The Chronicle: Speaking of the script, it must have been an incredibly dense read. The film is really complex. What was your initial reaction?

MM: “Am I this dumb?” [laughs]. But no, it was tricky. It’s very cerebral, obviously, and we’re talking about science fiction, which is always sort of a stretch—particularly for me because I can’t say I’m historically a science fiction fan. But it didn’t seem that far off. There was this ethical dilemma and all this sort of inner conflict within the characters, and it grabbed me. But from an actor’s point of view, I thought, “Wow, this is really interesting. This could be a really cool exercise in performance.” I mean, we’re trying to make eight minutes exciting over and over again.

The Chronicle: That sounds pretty difficult. How did you guys pull it off?

MM: The first sequence was the hardest to shoot because we had to get all the choreography right with all the people coming and going. It was maddening because once we did that, everything else was going to be set in stone because we actually shot the film in sequence. It progressively gains momentum because you keep adding pieces of the puzzle. Initially, it’s these two characters [who] are really in separate realities. It was really hard to shoot with Jake [Gyllenhaal] because everything he’s saying makes no sense to me, and everything I’m saying makes no sense to him. But then you start to see how [the characters] intersect. It had to be character driven.

If you didn’t care about what these characters are going through, then it doesn’t matter how cool your special effects are, and that’s true in any film.

The Chronicle: What was it like working with Jones? A lot of people really loved his last movie “Moon.”

MM: I love any kind of filmmaker who’s exciting and takes material from one genre and flips it on its sides. Duncan [is] somebody who’s a really great storyteller. I think he’s someone who does a lot with very little. He can take a big concept with little money and turn it on its head. I thought, “Well, gosh, I’ve never really dabbled in sci-fi, why not go on this endeavor with Duncan?”

The Chronicle: So what was it like being back in Chicago and filming after all these years? Was it fun shooting a film in

Millennium Park?

MM: This is such an amazing city. I was actually so surprised nobody had used the [Cloud Gate] Bean before [in a movie]. It’s so beautiful there. But when we were shooting there, I was kind of nostalgic about it because I could see Columbia across the way. I would say to Jake, “I used to go to school there!” It was a big decision for me to pack up and move and think, “Did I make the right decision?” When I was sitting there last year, staring at that Bean and making a movie, it was kind of a profound feeling. It was like, “Wow, I did it.” And it’s so cheesy, but I mean it.

“Source Code” opens in theaters April 1. Check local listings for showtimes.