Moon director Duncan Jones' Source Code is continually referenced as "Groundhog's Day with terrorists." But Jones says it's not true — and here's why. Minor spoilers ahead...

As you can see from the above video, Source Code deals with an alternate plane of existence, not just with time repeating itself. So how did they keep it from seeming like Groundhog Day? We asked them.

So how do you make something so repetitive interesting, and NOT a Groundhog Day remake with explosions?

Ben Ripley (screenwriter): Anyone who dies professionally is intriguing to me as a writer. At the end of these eight minutes, [the main character is] going to die. Whether it's being blown up, run over, or just disintegrating into pixels, that's his end point. So you want to challenge yourself and not have it [his death] be the same over time. And it is this sort of the Hitchcockian idea explored where you have a bomb under your chair and it goes off and surprises everybody. That's the first Source Code. In the second Source Code you know there's a bomb under the chair and it's just about the suspense of it all, so you sort of get to play both sides, which is great.

Duncan Jones: There's a real tough aspect to it as well, on the making it side where, you want to get the audience to care and invest themselves into what's happening to Colter Stevens (Jake Gyllenhaal) And also care when he dies. As a director I had to keep reminding myself that, "Okay, he's going to die and then he's going to come back, is the audience going to care that he died, knowing that he can come back?" And I think that was a real challenge. To make sure that there was enough reasons to make sure the audience was able to feel his frustrations for not being able to complete his mission. And feel his growing resentment about those people that put him in that predicament. I wanted the audience to care and empathize about him, even when they know that he's going to get another shot at this mission.