Duncan Jones is a bright, unaffected guy who seems determined to make science-fiction movies he wants to see.  I met him once, briefly, while he was working with the great Paul Hirsch to edit his new movie "Source Code" in Los Angeles.

Jake Gyllenhaal, on the other hand, I've been interviewing for the past decade now, ever since I talked to him for the first time at Sundance '01, where he was representing "Donnie Darko" along with his sister Maggie.

Together, the two of them seem quite proud of their twisty little thriller, a sort of sci-fi riff on the Hitchcock everyman movie, in which a regular guy finds himself in a crazy situation and has to puzzle his way out of it somehow.  The movie opened the SXSW Film Festival this year, and the audience seemed to have a blast with it.  Makes sense, because it's a movie that really works overtime to engage the audience and to entertain, but without empty thrills.

"Source Code" offers some significant creative challenges for the filmmakers and the performers, and I knew I wanted to talk to them about how they carefully constructed something that pays off in such rich and interesting ways, and how you build a character arc eight minutes at a time.

I think we were careful to avoid any significant spoilers in our conversation, but it's not really a film that's built around one big twist, so it's not the sort of thing that I think we could accidentally trip over in a discussion.  Instead, the film relies on the way it carefully and continually tweaks your expectations and your ideas about what you're watching and who these characters are.  The way the film pays off isn't one big firecracker out of nowhere, but is instead about the careful build-up to an eventual release that makes perfect emotional sense.  I like that the science in the film is far less important in terms of how it works than what it does to these people.  Those are the science-fiction stories I like the most, the ones that press us to examine our own humanity and the boundaries of it.

I'll also have interviews this week with Michelle Monaghan and Vera Farmiga, Jake's lovely co-stars in the film, but for today, we wanted to start with Jake and Duncan together.

"Source Code" opens in theaters everywhere April 1, 2011.