"It was an incoming call [to join the show], which is always nice any time you get one of those in this business ... saying 'Hey, Criminal Minds is interested. Are you?'" Rodriguez tells TVGuide.com. "I said, 'Yeah, I'd like to hear more about it.' I met the showrunner, Erica Messer ... and just fell in love with the idea of coming here. The vibe felt great. I love coming to work every day."
Rodriguez makes his debut on Wednesday's Season 12 premiere, when Alvez, an Army vet and Fugitive Task Force agent, tags along with the BAU to help collar those unsubs who broke out of prison in the Season 11 finale. Eight of the 13 have been caught over the summer, and one of the remaining five is the Crimson King — the title of the episode — who is Alvez's white whale.
"Before [Alvez] was in the Fugitive Task Force, he was an agent ... and his partner was one of [the Crimson King's] victims, who wasn't killed but was paralyzed by the Crimson King," Messer says. "He blames himself a little bit that he didn't stop this from happening and he also really has a lot of agency in catching this guy."
Exclusive Criminal Minds sneak peek: Garcia is so not into Alvez
Alvez's stint with the BAU was meant to be temporary — a meeting of brains and brawn, if you will — but the BAU makes him an offer to stay by the end of the episode. "He realizes at some point that the only way he's going to get [the Crimson King] is to basically join this team. That's sort of what the invitation is about: 'If you want to catch this guy, join us,'" Rodriguez says. "The allure of finding a different way to pursue him — cerebrally as opposed to just physically — he's now able to learn these new techniques with the BAU. He learns how to become a hunter mentally."
Unlike Alvez, Rodriguez was always going to be a series regular, ostensibly replacing Shemar Moore, which is the source of Garcia's (Kirsten Vangsness) ire. Of course, she's not actually peeved that Alvez is around — baby girl could never be that cold-blooded — she's just finally now forced to process Morgan's absence.
"[She] doesn't quite know what to do with this, because liking anyone could feel like a betrayal to Morgan," Messer says. "She has a little bit of a 'I'm not so sure what to do with this guy' runner. It's fun. It feels real and something different to play, certainly for Garcia, to not be accepting of him right away. But by the end of the episode, you know she's fond of him and this is going to be fun. She kind of plays against type for a while and I think that's going to be fun for the audience to see. She gets to go through the stages of it all."
For his part, Alvez isn't taking anything personally. "I think he knows right away that Garcia is missing this person very much," Rodriguez says. "He understands where it's all coming from. She doesn't have anything personal against him; she just wants her friend back." And so, he will have his own little fun with Garcia, keeping her guessing with his economical lifestyle — not entirely on purpose. You know how Garcia's desk is littered with tchotchkes? Yeah, Alvez's is the complete opposite.
"He lives a very sparse lifestyle, probably one fork, one knife, one spoon in the house. A bowl, a plate, one cup. He just really lives a simple life," Rodriguez says. "He's complex in that he's the kind of person that seems like he's hard to figure out but maybe really isn't. I think he's about some really basic things. I think he's about integrity and being passionate about his job. He served in the military for a while in a very specific unit as an Army major. I think you come through that life, there's a certain element of a rush that you become accustomed to. That's probably what led him to becoming a Fugitive Task Force guy for he FBI."
Exclusive: Jane Lynch is returning to Criminal Minds
As for Rodriguez, he's getting accustomed to being on another CBS procedural with a devoted fan base.
"You have a few people who are die-hard Derek Morgan fans that didn't want to see him go," he says. "The vast majority of what I've seen [from fans] has been positive, really welcoming. I think I'm bringing a fan base from my CSI: Miami days that if they weren't fans of the show already, they will be. I'm really not intimidated or shaken at all. It's like anything else. I have to earn my stripes."
See what else Rodriguez has to say about Luke Alvez in the video above. Season 12 of Criminal Minds premieres Wednesday at 9/8c on CBS.
(Full disclosure: TVGuide.com is owned by CBS.)