[WARNING: The following story contains spoilers about Wednesday's episode of Criminal Minds. Read at your own risk.]

Wednesday's Criminal Minds was a serious case of "oh, brother" for Dr. Tara Lewis (Aisha Tyler).

Expecting to meet up with her estranged, wayward brother Gabriel, she instead meets a man (played by Alimi Ballard) who not only believes he is Gabriel but somehow knows everything about their family. Fake Gabriel is actually Desmond, who has dissociative identity disorder, and was brainwashed by Mr. Scratch (Bodhi Elfman) into thinking he's Gabriel. Mr. Scratch had Real Gabriel (Terrence Terrell) tied up and recorded him screaming "Luke" on a video loop to taunt Tara.

No, he's not calling out for Alvez (Adam Rodriguez). It's all a reference to the Gospel of Luke, and Tara and Gabriel's relationship, which, as we learn, became strained after their alcoholic/suicidal father ordered a teen Gabriel to stay home and care for him, thus crushing Gabriel's Ivy League dreams and potential. Or, as Fake Gabriel dubs it, "the soft bigotry of low expectations from your own family." After Tara gets through to Desmond, the BAU saves Gabriel in the nick of time from a gun-rigged chair and flying nails (seriously).

Criminal Minds: Hotch's send-off was perfect in an imperfect situation

So is Mr. Scratch just going to target each BAU member? First Hotch (Thomas Gibson), now Tara. We caught up with Tyler to get the scoop on Mr. Scratch's dastardly plans, what this family breakthrough means for Tara, and her thoughts on all the cast changes this year.

We knew that Tara wasn't particularly close to her brother. Did you and Erica [Messer, the showrunner] talk about diving into that this season?
Aisha Tyler:
It was actually a conversation I had with Erica and Breen Frazier [who wrote the episode], probably when I came onto the show, about how we might start digging into my backstory if I was there. I originally only signed up for six episodes last year and now I'm in my second season! [Laughs] It was something like, "If we get a chance to extend your storyline, we'll delve more into your family." I think it was Breen who told me about it: "You're going to be meeting your brother." And it was kind of based on some stuff we had talked about when we created the character. I think I found out about this storyline the episode before we started shooting it.

Tara clearly loves her brother. Do you think she had any idea before this about what kind of role she played in Gabriel's life veering off path, even though she wasn't actively part of it?
Tyler:
I think that I understand that relationship because I have a sibling and there can be a natural competition between siblings, especially if one of them is kind of a Type A or an apple polisher. ... [Tara] has this very fraught relationship with her brother, who's smart and capable and thoughtful but hasn't really lived a conventional life. I think a lot of times, there's a lot of guilt that comes from both sides of the sibling relationship when you both don't follow the same path, and one feels they've left the other behind and the other one feels like they've been left behind. I really understood that relationship. It's a fraught one, but she loves him. You see in the show how deeply she cares about him and how some of the choices she made negatively and positively affected their relationship.

Aisha Tyler and Matthew Gray Gubler, Criminal MindsAisha Tyler and Matthew Gray Gubler, Criminal Minds


She has that conversation about how she was the prodigal son with Desmond, not Gabriel, and relieved him of that guilt. As far as what was shown, she hasn't had that conversation with Gabriel yet, but is it safe to assume she will?
Tyler:
Yeah, I think she's going to have a lot of conversations with him and her father. I think all of their relationships are going to evolve and change in a dynamic way. This is definitely a breakthrough for her personally with her family relationships and getting to understand her father more and her brother more and herself more. It was very interesting to play that because she was interacting with this guy who's pretending to be her brother, and she's treating him like her brother, and they're having a lot of conversations that she actually needs to have with her actual brother.

It's a good warm-up for the real thing.
Tyler:
[Laughs] Yeah, exactly! Now she knows what to say.

This is the first case to hit Tara personally. How will it affect her going forward?
Tyler:
This is the first case on the show that's hit her personally, but we spent a lot of time talking about who Tara is, what her experiences have been and what brought her to the FBI and generally with profiling. ... I think it won't change the way she works. Hopefully it'll change her relationship with her family. But I think what you get to see is what a good profiler she is and how well she understands sociopathy and a little bit of what might've motivated her to get into the job. She cares very deeply about the work that she does and obviously if you watched last season, you know that she specializes in the psychology of the sociopath and the serial killer. I think that understanding of sociopathy really helps her crack this case.

Will we see Gabriel and her dad again? It ends on a hopeful note for them.
Tyler: I hope so. I think so. I think it'll be really interesting because I didn't get to spend a lot of time with the guy who plays my actual brother. I spent a lot of time with the guy who plays my pretend brother, who is a pretty extraordinary actor, and we were all lamenting we might not get to spend time with him again.

She can visit Desmond.
Tyler:
Yeah, right? You never know. Maybe he has more info on Mr. Scratch.

Mr. Scratch must have a bigger plan in mind, right? I refuse to believe that he think he'd get you guys with flying nails.
Tyler:
No, no, no, he's a game player for sure. I think he's going to haunt the BAU for quite a while.

Is he just going to target each person through a relative? Should we be worried about Reid's mom, since Jane Lynch is returning?
Tyler:
I can't tell you that! ... Mr. Scratch is a very prominent figure and I think he's probably going to touch every member of the BAU by the time the season ends. That's all I can say. We hear a little bit [from producers], but we don't get a season-long spoiler, so I honestly don't know a lot, but you will see him again soon.

Damon Gupton joins you guys next week. What can you say tease about Agent Stephen Walker?
Tyler:
Damon's just a great guy and a great actor and I think a really great addition to the team. [Stephen] is a longtime FBI agent with a particular set of skills and joins us and we're thrilled to have him. [Damon's] a lovely guy and incredibly talented.

There's been a lot of change, not just this season but this calendar year, with all the cast upheaval. What has that been like on your end?
Tyler:
There's a lot to adjust to. I think it's hard. As someone who came on last year, I know what it's like. ... We're in Season 12 and we've had a lot of changes this year, but what's been thrilling is how well the team's working together and what a great community and a great environment we've got there. I think in the real world, the real workplace, people change [jobs] all the time and come and go, and you adjust. What I can tell you is that we loved what we had before and we're really loving what's happening right now.

Criminal Minds airs Wednesdays at 9/8c on CBS.

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