Linda Barnes (Kim Rhodes) has only just begun to wreak her havoc on Criminal Minds.

The Assistant Director of National Security was responsible for disbanding Simmons' (Daniel Henney) previous team and now she's coming for the BAU. She's already managed to put Prentiss (Paget Brewster) on administrative leave, forcing J.J. (A.J. Cook) to be temporary lead of the team — even though Barnes is really the one pulling the strings.

Criminal Minds Exclusive: Linda Barnes Has Prentiss in Her Crosshairs

In Wednesday's episode, "Annihilator," J.J. will take the team out on their first case without Prentiss, but has very serious reservations about taking the job under the circumstances. Even though Rossi (Joe Mantegna) tries to assure her, the pressure is on for J.J. and the rest of the team to be on perfect behavior or risk Barnes succeeding in splitting the team apart.

TV Guide talked to Criminal Minds' Kirsten Vangsness, who plays the team's eagle-eyed cyber guru Garcia, about how Barnes is going to affect the team and whether the BAU can withstand interference on this level.

Kirsten Vangness, Criminal Minds

What is it like to have Linda Barnes babysitting this next case?
Kirsten Vangsness: Oh my god! She is the Dolores Umbridge of the BAU, if you're a Harry Potter fan. She is coming in and ruining Christmas in such a way that I hate it so much. It's really sad because she's a nice person in real life...All of us were actively scared [during the table read]. It doesn't stop. This is the awful episode that happens that you need to have happen. It's a great episode but I don't think that people will enjoy what's going down. I didn't at all...It's a beautiful build up to the next episodes we have. This job is based on everyone being intuitive and having each other's back. How do you do that when you have this person who is based entirely on her neck up, entirely on her brain? She is not thoughtful about things. It's hard.

How is the team reacting to J.J. being head of the group, considering the circumstances?
Vangsness: It's weird. It's weird for her. I don't think she wants that role. I think that she's doing the best that she can in it. It's very hard to do when you have this other woman. She's the acting head but Barnes is all up in her grill. I think we've all had this experience...We've all had the experience where you've had a job that you've been tasked to do and then there's this oppressive energy that's all up in our grill that makes it impossible to do the job well. I think that's causing [J.J.] a lot of conflict because she can't do things the way she wants to do it. This builds beautifully for what happens next.

Criminal Minds Exclusive: Is Linda Barnes Trying to Split Up the BAU?

How is it going to be different for Garcia? She's not in the field and she has a bird's eye view of everything that's going on.
Vangsness: There's a little sprinkling of how bad it gets, and then it gets a million times worse. You will get plenty of her feelings about the situation. This is a build that just keeps building. The episode that will air on March 14 — you need this episode in order to really inform it. This is one of those classic, cool the case and then the Barnes of it all on top of it [episodes]. You get to see people outside of their natural habitat. You get to see more of that in other episodes. Paget [Brewster, Prentiss] is still in the episode, she's just not with the team. You have other team members trying to be there for her and with her. You will see everyone in environments that you'd never to expect. We were shooting on locations.

The entire team thinks of the BAU as family, but Garcia in particular is very sensitive to any changes or fluctuation within the team. How badly is she spiraling at the prospect that the team could be disbanded?
Vangsness: It's the worst. When it starts going you'll be like, "Oh, that's what she meant." It's the worst ever. It's terrible. It's been really fun because we really do like each other so much...When you see the contrast of what it could be like if, you know, there's going to be a time when the show's not on the air. We're all exquisitely aware of the fact that we get to be on this train with each other. When you get the contrast at the character to see what it's like to not have those people around or not around in the way that you're used to, it's painful. It affects Garcia a lot. Garcia couldn't do that job if she didn't have the connections that she has with them. She's so empathic and if you take away her ability to be able to commiserate or to touch base with someone, it's harder for her to do her job. She needs that. It's really scary when that leaves her.

The audience and Prentiss know that Barnes is specifically going after Reid and Rossi. How obvious is that going to be to the rest of the team once she's embedded with them?
Vangesness: It's going to get really obvious. The great thing about the way that the show is written is that nobody is completely without — you know, there's a lot of choices. We all make choices every day and some of those choices we 1000 percent stand behind and some of them we go, "Well, that was a last minute thing" or "Well, I did the best I could with what I had." Our team has made a series of choices in the past and in the blink of an eye because you have to and they're easy to count on. If you don't know, you could twist it or decide to use it to your advantage. I think Barnes is very good at that. She is very shrewd. We have such a good actor playing that role. They give her plenty of ammo by accident.

Is there any reason for us to like Linda Barnes?
Vangsness: Linda Barnes is responsible for some really wonderful stuff that's going to go down. Unfortunately, she has to bear the brunt of it. I call people like that "my spiritual friends." She's our spiritual friend in that we're going to learn our lessons and stuff. Everyone should like her because if it wasn't for Linda Barnes we wouldn't have some cool stuff happening. Buffy the Vampire Slayer doesn't exist without the big bads.

Criminal Minds airs Wednesdays at 10/9c on CBS.

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