Jeanne Tripplehorn Jeanne Tripplehorn

There will be a new face joining Criminal Minds' Behavioral Analysis Unit this fall.

Jeanne Tripplehorn joins the cast in Season 8 as Alex Blake, a veteran FBI agent who specializes in linguistics. She fills the void of the departing Emily Prentiss after Paget Brewster opted to leave the series at the end of last season. Some viewers may be suspicious of the new character, but executive producer Erica Messer tells that that's just fine — apparently a few of the team members will share that feeling.

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"When we meet Alex Blake, it is also Morgan [Shemar Moore] and Garcia's first time meeting her because they have actually been away on temporary duty in London," Messer says. "It allows Garcia [Kirsten Vangness] to ask all those questions that the audience would want to know."

Read on for more of Messer's thoughts about Alex's back story, viewer backlash, and whether or not any romantic sparks will fly between Alex and her co-workers. Plus: Get some dirt on this season's first unsub!

You originally said you didn't want to replace Prentiss right away. What changed?
Erica Messer:
At the end of last season, we were all kind of feeling like we [should] let the loss of Prentiss sink in a little bit, much like it did when Mandy [Patinkin] left. We thought, given the history of the show, that's what we'd be doing again. But it's not just up to us. There's a whole lot of people at the studio and network who really wanted us to hit the ground running with a new character. So, that's what we're doing, and Jeanne Tripplehorn is fantastic.

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What can you tell us about her character?
Her character's name is Alex Blake, and she has a history with the bureau as an agent. Her specialty is linguistics. She is the expert linguist that people like Reid [Matthew Gray Gubler] learned from.

Do they have an actual history?
They do. In addition to being a supervisory special agent, she also is a professor at Georgetown University, and Reid has even guest-lectured at her forensic linguistics class before. So they have a nice professional history together.

How do we meet Alex?
It has been a couple of months. Prentiss didn't just quit the day after the wedding. It was a process. [She was] transferred elsewhere, [the team] was doing interviews for months to find the right fit. It all took a lot of time. So, when we meet Alex Blake, it is also Morgan and Garcia's first time meeting her because they have actually been away on temporary duty in London. When they return, the rest of the team has already been on a case with her, but it's Morgan and Garcia's first time meeting her and working with her.  It allows Garcia to ask all those questions that the audience would want to know.

Is there an element of Garcia not trusting the new kid?
Yeah. [Alex] is really smart and capable and very credible, and I think there's a threat to that. This team existed without her, so it's not like she's come to save the day. Buy she is a very smart, capable woman joining the team. It's not [necessarily] distrust, but it's just, "I need to get to know this person who's going to be sitting at this table with me for the next however many years." There's a very real dynamic there from both Morgan and Garcia. Those things happen when you first meet a coworker.

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Perhaps it's good she has an ally in Reid.
Yeah. And there's a little bit of shorthand with them on the professional side. Just the fact that they have known one another for a little while outside of the bureau helps. It's all still professionally based, but no it definitely helps.

Would you like to go ahead and quash any Hotch-Alex hookup theories now?
I always feel like when you get your heroes involved romantically, it just changes the show so much. I know everybody loved the Prentiss-Hotch [dynamic], and that's why it looked the way it did in the finale with them dancing. I wanted that shout out to go to everybody — that these two, at another time, maybe would have happened. In another time maybe this still will happen. But while they're working together, it's not going to happen. So I feel pretty strongly about that as a rule. But [Alex] is in a relationship. Hotch [Thomas Gibson] is still in a relationship with Beth.

Will we meet Alex's significant other?
I think, eventually, we will see that person. Less is more with a lot of these new characters. You want them to remain a little bit of a mystery. Prentiss was a mystery for far, far too long, but then we actually wrote to that in Season 6. It's rare that we meet anybody's significant other. We knew Haley from the pilot. We know Beth because we wanted to see Hotch smile again. We met Rossi's first ex. I just cited examples of it, but it's not something that we do a lot. I can't see us going home with her as much as we did with Prentiss.

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When Prentiss and JJ (A.J. Cook) exited the show a couple seasons ago, fans weren't very accepting of Rachel Nichols' character. Do you worry about a similar backlash this time around?
I worry about a lot of things and that is certainly one of them. Prentiss was such a huge presence on the series and what helps everyone out a little bit is that it was her choice to go. It was actually Paget's choice to leave, and then we wrote in that it was Prentiss's choice to leave. That helps when the actual off -screen backstory can mimic what's happening on-screen.

The challenge in history not repeating itself this time around was to make sure that whoever the new team member is has a lot of credibility. It was difficult to do that with Rachel Nichols' character because she was so young.  Yes, she had a very specific skillset — she was the daughter of a serial killer — but we never had a chance to really explore that with her. I just feel like when you bring a trainee into the elite team, people are going to really rebel against that. So, [Alex] is a very seasoned agent who is joining the elite team and her road here has been well-earned.

Are you working with any kind of theme this season?
We are a little bit. Right now it's feeling like there's a lot of history coming back up. History and history repeating. The season kicks off with an unsub who is back. He had disappeared for a while and he's back killing. So it sort of stems from that idea that even the bad guys are sort of learning from the past.

When we spoke at the end of last season, you mentioned wanting to tell some origin stories this season. Is that still the plan?
  Yeah. We've talked about it. It feels like it's in the air doing The Avengers kind of thing where you sort of learn everybody's origin and how they got together. I'd like to still go there, and given the fact that this is a season we're introducing a new character and you get to see her backstory with the bureau, it feels like we want to get that from all of our characters. That's something we're still going to explore. It's a little bit early on in terms of finding all of those arcs for the season, but we're talking about all of that now.

Criminal Minds airs Wednesdays at 9/8c on CBS this fall. What do you think of Tripplehorn's character?