We've been through this before, right?

New season of a long running show is about to kick off, but the new face to the show is a very familiar one to TV viewers. For Criminal Minds Season 10 it's Jennifer Love Hewitt (Party of Five, Ghost Whisperer), as she joins the cast as Kate Callahan.

Executive Producer Erica Messer told me yesterday that she and her writers had Callahan start off on the right foot with the group from the start, explaining why in the exclusive interview below.

Also, we talked about personal stories to come and, this being Criminal Minds, some of the cases that just may have you looking away from your TV at times...

TV Fanatic: I really like how you integrated Jennifer Love Hewitt into the show in this premiere. She seems to get along with everybody pretty quick but was that your design or was that more organic just because of who Jennifer is?

Erica Messer: I think it’s a combination of both. She’s so lovely it’s hard to not like her and then it feels like it would be playing something really false to have any kind of conflict there and also it’s a little bit of a learning curve when we introduced Blake back in season 8 [and] there was a little bit of internal conflict.

The very nature of somebody new coming into our family and having a little bit of conflict with somebody was not really embraced by the audience and my fear with that was it kind of stuck with her longer than intended. It was actually just meant to bring another layer and a shade to it but instead I felt like it sort of had people not excited about her character and I certainly didn’t want to do that again. So this was a little combination of learning from the past but also just also the nature of who Love Hewitt is. She’s lovely on screen and off and the team, you know it seems only right for them to connect with her on the great and they certainly are connecting with her on the great.

TVF: That said, did you go about making sure that Kate Callahan was a little different than what we’ve seen in the past with other characters?

EM: Yeah, at this point we’ve had the show for so long and the audience definitely wants to come back and watch the team that they’ve known and loved for so long. So if we’re going to bring somebody new into that family the idea was they have to have a little bit of a different voice and a different skill set because they’re coming into a very established world…what I did with it was give her the background of going undercover and having to interact with bad guys on a long term basis and that’s something right off the bat that our team doesn’t have to do.

They go in every week and they find the bad guy and they bring him to justice weekly and the idea is there’s a whole other group at the FBI that doesn’t have that and I don’t know if the grass is greener there or not because what they have to do is dive in, sometimes for months, to really lure in these bad guys and it felt like why not have her character know the world, be familiar with the worst of the worst but she’s just had to deal with it in a completely different way and she pretty much says that to Hotch in their first interaction. “You find a bad guy every week. How do you not take that home with you?”

TVF: Would you say at least in the first episodes with her, is that her learning curve? How to shake it off when she’s doing this in a much faster pace than what she’s used to?

EM: It will sort of culminate by the end of the season. You’ll get the idea that it’s easier said than done to just let something go and Hotch gives you that look at the end of the premiere that he’s not letting it go either. So it’s not something that we will touch base with throughout the episodes but sort of the feeling of season 10 will be they don’t all let things go.

TVF: Let’s talk about some of the cases this season. Is there a difference in how you’re approaching them now or is it kind of business as usual?

EM: It’s a little bit business as usual which is what we all say behind the scenes - BAU. The BAU is business as usual because that’s what works and that’s what people tune in for every week but that said the guy in the premiere is taking off limbs and it’s got its creepiness to it but when we screened it, it was like, ‘Welcome back and here we are.’

The second episode is more of the same and then the third episode is a little bit of a departure because we’re doing a massive plane wreck and it turns out it’s not terrorism the way you would anticipate it…visually it feels like a feature and we really went big and we usually don’t go that big that early in the season for a number of reasons but CBS was very much behind it so we went for it.

Then episode 4, Breen Frazier wrote it, and it’s just the creepiest one we’ve ever done because it involves bugs. We were sitting in the screening and everybody was just squirming and like, ‘Oh, my God. I can’t look at the screen,’ but when you think about what we’ve done for over 200 episodes, it’s pretty gnarly and we can all sit through that but when you put a bunch of cockroaches on the screen all of a sudden we can’t watch an the episode without screaming, in its own right.

TVF: Will we be getting some personal stories with our characters, too?

EM: Yeah, by episode 9 you’re going to meet someone in Rossi’s life and I’ll just leave it at that as a little tease and, you know, Joe Mantegna was best friends with Meshach Taylor so when Meshach died in July Joe said ‘can we find a way to finish that story that we had started 2 or 3 years ago?’ So we’re doing that and it’s really a heartbreaking episode.

It’ll be episode 12 and it was so important for Joe to finish off that story, I think, emotionally for himself and also for just the memory of Meshach and the fact that the last thing he did as an actor was this series and Joe couldn’t be happier about that. That they got to work together after all these years, you know they worked together some 40 some years ago and here they were again for the very last thing that Meshach did. So that’s a real big episode.

TVF: What about with the rest of our cast? I know it’s not the thrust of the show but is the plan to give them some personal stories throughout the season?

EM: Yeah. That’s always our plan. I always feel like it’s like giving your children ice cream, you’ve got to make sure there’s enough to go around or nobody can have it and we, for personal stories, we’ll come up with something incredibly dramatic and then it might just be too devastating.

Like a couple years ago when we killed Reid’s girlfriend. We finally gave him a girlfriend and then we killed her and it was just like, ‘Okay. That might have been too much. Now we’re sad we did that.’ So you really have to think about what that does to a character because that character is so grounded they seem real and then you need to say, ‘Okay. What would that do? If Reed was my friend how would you help him out of it?’ you know?

TVF: And I have to ask – and I know you address this in the opening dialogue of the premiere – but any chance of Emily Prentiss coming back? Any plans you can talk of at this point?

EM: I wish. I wish. We don’t really have an episode 200 this year that would definitely point in that direction and she’s got an Amazon show now so it becomes a little bit more of a production issue than just an availability issue but you know we love her and we would love to have her back whenever she wants to play but the reality of it is it’s harder than we’d like it to be.

Criminal Minds Season 10 Episode 1 airs tonight at 9/8 on CBS. 

Jim Halterman is the West Coast Editor of TV Fanatic and the owner of JimHalterman.com. Follow him on Twitter.