Duncan Jones tells us what really happened at the end of Source Code

What on Earth happened at the end of Source Code? When Jake Gyllenhaal takes over your body, what happens to your mind? Is this a religious movie? Moon director Duncan Jones answers all our deepest questions about his new movie.

He also tells us a couple of Easter eggs to look out for. Warning: Heavy spoilers ahead!

Here's a full interview with Jones, but we've pulled out some of the good bits and added on a few Easter Eggs below.

What happened to Sean Fentress, the teacher whose body Colter Stevens inhabits?

Jones: So the idea is the Colter Stevens is now inhabiting the body of Sean Fentress. If that is the case, and Colter Stevens has been able to get on the train and stop the bomb from going off, then that means Colter Stevens never needed to be sent back to find out why the train blew up. Which means that somewhere back at the facility where Goodwin works, there is a Colter Stevens who's never been sent on a mission yet. So the idea is that now, in this parallel reality we have a Colter Stevens inhabiting Fentress and a Colter Stevens waiting in a facility where Goodwin works who has not yet been sent on a mission.

OK, we admit, he kind of snuck around the question here. But, in the SXSW Q&A he finally just admitted that Sean Fentress, the Fentress that Stevens is inhabiting, is dead. So there you have it. He's dead. And he's in another universe, not dead. But he cannot exist with Stevens in his body, apparently.

How The Nuclear Boy Scout documentary influenced Source Code's Villain

Jones: It was about a guy in the Midwest and this a true story. What he did was he actually built his own breeder reactor in the backyard of his mom's house, that irradiated the whole neighborhood. And this happened about 15 years ago, not that long ago. He was incredibly smart and had absolutely no sense of right and wrong. He was just a very, very strange, very scary kid. And I thought that was an interesting idea that you could have someone who was smart enough to be able to build something like that, and his main reason to do it is, "Well I know how to do it, so I'll do it." And no sense of whether he should do it or shouldn't do it. I thought that was a very interesting starting point for that character.

How Many Source Codes are in the film?

Jones: It depends on how you count them. We follow the story of six of them. But there's a period in the film where Colter is being sent back again and again and again. So if you count them, there are either eight or nine. But there are six where we actually follow the narrative.

Is the final Source Code Heaven?

Jones: Heavenly — but in my opinion he's not going to heaven, he's jumped bodies. He's now on a separate parallel reality and he's able to live out his life in the body of Sean Fentress.

Who was the voice of Colter Stevens' dad on the phone?

Quantum Leap's star Scott Bakula! And if you listen closely you can even hear him say the words "Oh Boy!" Jones admitted that QL was a big influence on the writing and on the film. The instance where Coulter sees himself in the mirror in the body of Fentress, that's a very big QL moment. Jones explains, ‘Wouldn't it be great if Scott Bakula did that?' And he's the right age and the tenor of his voice is definitely a supporting, nurturing voice that he has. We brought him in and he was so lovely and willing to take it seriously, and he got why we wanted to have him do it. It was great, really lovely to have him do it."

What Source Code shares with Moon

The same song is in both films! On Monaghan's phone and on Sam Rockwell's alarm clock!

Jones: That is by a guy named Chesney Hawkes. It was a one hit wonder [called "The One and Only"] in the UK when I was growing up. It's an in joke in the UK, everyone in the UK knows that song. I used it in Moon it's actually the alarm clock that Sam Bell has. I used it as the ring tone in this, and don't be surprised if you hear it in my next film somewhere. (Here's the song)

Duncan Jones tells us what really happened at the end of Source Code

How did they make Michelle Monaghan's face melt?

It was all practical, as the actress revealed to us:

Monaghan: That really happened, they put a giant wind fan on me. It was the last night of filming and they brought in the special effects to do that shot and said "You don't want to do that do you?" And I said, "Of course I do, that's awesome!" We probably shot it four or five times [with her face in the wind machine] And they played it back in slow motion. It as seriously the ugliest thing I've ever seen. Everyone was saying "oooh." My lip was over my gum, then they paused it and I thought holy shit I need braces. It was just the craziest thing. I must have been red for two hours, but it was a really fun effect to do. Later when I saw it in the film I was surprised because I didn't think they were going to use it [as is] I thought they were going to fix my lips, but it's cool that they left it like that, because that's how we shot it! I'm glad I did it.

Video by G. Jesse Martinez