On what will happen to Zach this season, based on his murder confession during the season finale and his eventual departure:

Zach's not really going anywhere. We will see him again throughout Season 4 in certain circumstances. We actually just shot an episode where he got out and helped us solve something and I had to put him back into prison.

On what's in store for Bones and Booth in Season 4:

Right off the bat, it's really focusing on their relationship and how that affects how they solve crimes and how they move forward with whatever case they're working on. We honor and support the character work, and that's what we strive for on the show, which makes us different from other procedurals out there. I know Hart [Hanson, the show's creator] has ideas for some fantasy episodes for getting the two of them in bed. Maybe going into Booth's past a little bit and seeing where he came from and seeing how that affects his relationship with her.

On "Bones" being more widely viewed than his two previous series that had a cult following:

I think what's great about "Bones" is that it's been embraced by the critics and by a following of people that have really supported us from the beginning, which in retrospect is the same as the other shows that I was on. We still remain pretty much under the radar. I still believe there's a lot of growth for the show. I think the beauty has been its gradual increase.

On whether there was immediate chemistry between him and Emily Deschanel, who plays Brennan:

When we first did a test, we had one woman in mind who I thought was going to get the role. I went in and read with her and another girl, and Emily, too. And after Emily tested, [producers] saw something in the test that sparked, and that was the girl. And then you work at it. It's great to have someone who wants to work at it together, and that's what we do.

On what draws Booth and Bones to each other:

They're very much alike in a lot of ways, but they're much not alike, too. I think there's that little kid inside Booth that she really enjoys, because maybe she lost a part of that because she's so straight and serious and very literal.

On whether the show has made him an armchair detective:

I think I'm more interested in the character work with Booth.

On how Booth will evolve this season:

It will really get back to Booth's past. We'll see his apartment. We'll see where he's living this year. One specific idea that I have that I really want to exploit is that Booth is very charming on the outside. He's got all his shields up, but he's a guy who was an Army ranger. He was tortured. He got hit in the shins. It'd be nice to see how Booth gets ready in the morning. See him kind of start the day and see how hard it is for him. When we do see him, he's always kind of on the move. He has all his stuff that protects him, but what he's really like underneath is some good stuff, and I think we'll exploit that this year.

On what impact him being a producer has on the show's story lines:

It's really a lot of character stuff and ideas, and implementing them into the story line or scripts.

On following the career path of Bruce Willis, an actor whose first big break was on "Moonlighting" as a detective with major sexual chemistry between him and his partner:

I think it was the second season of "Bones," I bumped into him and he couldn't have been nicer. He was very cool. He said, "You're doing a great job." And I said, "Well, I'm just following your lead. I have such high respect for you." It was a really cool moment.