Jeanne Tripplehorn

Jeanne Tripplehorn just wants you to like her — or her Criminal Minds character, at least.

The Big Love alum will return to TV Wednesday on the CBS drama (9/8c) as new BAU member Alex Blake, and all she can think about is what will happen after the episode is over.

"The fan base is huge for this show and I am honestly nervous about what they will think of Alex," she tells TVGuide.com. "A show bringing somebody new in on the eighth season, especially if you've been [a fan] since Season 1 — people will have their opinions. I think the fans are incredible and I respect this insanely rabid fan base the show has, and I do want them to accept Alex. I hope they like her."

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Tripplehorn's concerns aren't unjustified. The last time Criminal Minds added a new cast member — Rachel Nichols' Ashley Seaver in Season 6 — it sparked a near-revolt among fans, who were still miffed about A.J. Cook's and Paget Brewster's exits at the hands of CBS. (Both returned in Season 7 and Nichols was let go, with Brewster leaving again in the season finale.) Fans' biggest gripe about Seaver: She was a cadet. "It was crazy how hardcore they rebelled against her being a newbie," showrunner and executive producer Erica Messer says. "But that was a lesson. We learned from that and we did the opposite with Alex."

A seasoned FBI agent, Alex has spent her whole career in the Bureau and has a second career as a linguistics professor at Georgetown. She has a Skype relationship with her husband, who's with Doctors Without Borders, and she knows Reid (Matthew Gray Gubler), who has guest-lectured in her classes, and Hotch (Thomas Gibson) and Rossi (Joe Mantegna) from their lengthy careers. "The writers and producers really care about what the fans think, and we talked a lot about how she'd be introduced," Tripplehorn says. "They knew: We have to introduce Alex in a proper way and make sure that she doesn't alienate everybody and they can work alongside each other while also showing what she's like and what she's capable of."

It won't be one big happy family right away. The premiere picks up several months after the events of the Season 7 finale, with Alex already working at the BAU and meeting Morgan (Shemar Moore) and Garcia (Kirsten Vangsness) for the first time after they return from an assignment in London. And let's just say Garcia suffers a massive case of "open mouth, insert foot" before a totally not-amused Alex. "It's not the best first impression, but the good thing is they start over again in the end," Tripplehorn says. "Now, as we're shooting [more episodes], nice friendships are developing within the group."

Left out of the lovefest is Strauss (Jayne Atkinson), who let Alex take the fall in the Amerithrax case after a linguistics error. That deterred Alex's admittance into the BAU and she has absolutely no qualms about showing her disdain for Strauss. "They lock horns and they're not finished yet," Tripplehorn says. "They're at a détente right now. I don't know how they're gonna explore it, but I love that Alex is upfront and not afraid to say what's on her mind."

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Alex's often-stern, hard-nosed temperament shouldn't be mistaken for aloofness though. "She is warm and altruistic, which hopefully you'll see throughout the season," Tripplehorn says. "But you can't forget that she's career FBI and ... she's a Type-Triple A, so she's hardened and tough. She wants to rid the world of evil. She's a hard worker and she's driven and she's completely different from Barb on Big Love! So that's been fun too."

But the disparity between a sister-wife and an FBI agent wasn't what attracted Tripplehorn to Minds. Although the actress, who guest-starred on New Girl last season, ultimately wants to do a comedy, Minds is the "right job for right now" as she raises her 10-year-old son. "Really for the next eight years until he goes to college, I'm trying to stay as close to home as I can," she says. "There aren't a lot of productions that shoot here [in L.A.]. Just like Big Love was, this job is a godsend for a working mother. There are a lot of women who work on this show ... and it's a family here. All the crew has been here forever and ever. It's a great gig. Character-wise, in tone of project, genre — Alex Blake is exactly what I should be doing right now."

Not a regular connoisseur of crime procedurals, Tripplehorn did not previously watch Minds, but screened all of Season 7 after she joined the show.

"It's a classic crime drama, in that it follows this winning formula," she says. "I get why people watch these shows because there's something almost comforting because you know what you're gonna get as far as pacing. It's got this rhythm that is established. I want to see Seasons 1 and 2 simply because it was so long ago."

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The first two seasons, of course, starred original cast member Mandy Patinkin, who abruptly left in Season 3, troubled by the show's dark nature. He recently expounded on his previous comments, telling New York Magazine that Minds was "destructive to my soul." Tripplehorn, however, says the show's gruesomeness was never a factor in her decision to sign on. "I was drawn to the women who run the show, the writers, the cast, the crew," she says. "So I don't really give [the violence] much thought. But the world is violent, and this is TV. It's fake. I can shake hands with all the corpses in the morgue."

She continues: "But I was fascinated by the true crime stories when I was a little girl — Helter Skelter, the Zodiac killer. [I read] all the crime magazines. I don't know what that says about me! So in a way, it's almost like the young girl in me is tapped into this character of Alex Blake. So this is the perfect job."

Criminal Minds premieres Wednesday at 9/8c on CBS.