[WARNING: The following story contains spoilers about Wednesday's Season 12 finale of Criminal Minds. Read at your own risk.]

Reid and his mom may be safe and sound on Criminal Minds, but the same can't be said for the rest of the BAU.

Season 12 concluded Wednesday with the show's first true cliffhanger since Season 3. After a bearded Morgan (Shemar Moore) returned to show his former team a sketchy text message purportedly from Garcia (Kirsten Vangsness), the BAU deduces that it was from Mr. Scratch (Bodhi Elfman) and sets out to his location.

Naturally, it's a trap. Out shoots a bunch of spike strips that derail their SUVs -- just in time for an 18-wheeler to plow into them. Alvez's (Adam Rodriguez) SUV, consisting of JJ (A.J. Cook) and Walker (Damon Gupton), gets swiped, but Rossi's (Joe Mantegna) ride, with Prentiss (Paget Brewster) and Lewis (Aisha Tyler) inside, takes the brunt of the impact as the show cuts to black.

Reid (Matthew Gray Gubler) is the only field agent we can presume to be safe after successfully facing off in another psychological cat-and-mouse game with Cat Adams (Aubrey Plaza), who turns out to not only be partners with Lindsey Vaughn (Gia Mantegna), but lovers too. Cat gives Reid four hours to guess "a secret [he'll] never admit to" in order to save his mom Diana (Jane Lynch), and she tries to throw him off by saying she's pregnant with his baby, inseminated with sperm Lindsey procured after she drugged Reid in Mexico and pretended to be his dearly departed Maeve.

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Thankfully, that soapy twist is not true, but Cat is pregnant -- with the baby of a guard who worked both her and Reid's prisons. And off goes the light bulb for Reid: His dirty little "secret" is that he enjoyed poisoning his fellow inmates. Their full conversation, including Cat's confession about her pregnancy, is played for Lindsey, who had no idea Cat was with child and surrenders herself -- and Diana -- to the BAU.

So now Reid is 2-for-2 versus Cat. But could her psychoanalysis of him be true? Can he return to the BAU? And why didn't we get a scene between him and Morgan? Oh, and who survived that pileup? Showrunner Erica Messer answers our burning questions and teases Season 13 below.

When did you guys decide to do this cliffhanger?
Erica Messer:
Well, it's tricky. We're usually ahead of the game in terms of breaking stories and stuff and we really had to be this year because of the arc for Dr. Reid. We always sort of knew the ending of the Reid of it all with Aubrey and that beautiful stuff with Gia Mantegna. But we kept saying, "That's going to be tied up in a neat bow, but it feels like the season of unexpected twists for us," and it felt like we earned the right to do a proper cliffhanger this year of all years. We started kicking it around and pitching it to the studio and network and they loved it, so we went with it.

A car accident out of nowhere is often classic cliffhanger-y, but this felt like, this wasn't a bomb or anything like that; it was them talking about once we get to Scratch's hideout, he's going to have traps within traps within traps. We're expecting once they get out of the car at Scratch's hideout it's going to be bad news, but the fact that it was before they could even get there -- that that was where the trap was -- is frightening and unexpected. They were not prepared for it. We probably didn't decide on that completely until February and we shot it in March.

Were you going to finish the Scratch arc completely this season and then changed your mind in February to do the cliffhanger?
Messer:
We had debated whether we wanted Scratch to be around. He's such a great bad guy that if we got rid of him, it's that thing of you have to create a new one essentially to always be that threat to the team. We just felt like maybe we weren't done with him yet, so that's why we have him not only finishing 12 but launching us into 13.

Did everyone survive?
Messer:
I hope so! [Laughs] That's always the trick of those kinds of endings. If we do make a change, chances are it would be because of that accident. The writers start June 5 and that's something we'll hit the ground running with, with what happens after that accident.

I guess the better question is: Is everyone returning next season?
Messer:
Again, I certainly hope so. I love this group. If I've learned anything in all these 13 years it's you can't truly prepare for anything. [Laughs] So I can't say yay or nay to that. I don't have all the control there, but I certainly hope so. I love the whole gang. I certainly hope we know by June 5 when our writers' room starts back up. We can't really move forward until we know the answer to all those questions. We've certainly started seasons before with actors' deals not done, but they were always in a good faith negotiation place, which I feel like is happening this year as well.

People aren't going to be worried about Reid or Garcia because they weren't in the car and obviously we have to acknowledge what Dr. Reid has been through this year. We can't just pretend that didn't happen, but at the same time, we want to make sure it feels realistic, that he's getting some help next season and that kind of stuff. It'll be a change next season no matter what because we're dealing with the aftermath of what Scratch just did and what happened to our hero in prison that whole time.

Paget Brewster, Shemar Moore and Kirsten Vangsness, Criminal MindsPaget Brewster, Shemar Moore and Kirsten Vangsness, Criminal Minds



Is there any connection between Scratch, Cat and Lindsey? Are those two stories going to tie together in any way next year?
Messer:
They might a little bit. The whole time we had to think it's Scratch [who framed Reid] because who else would have it out for the team like this, and he had succeeded in so many bad things this season already that it felt like a natural thing that that would be the path they would be on. ... But the fact that it was Cat getting Reid back with the help of Gia's character, which was just fun to have that throwback to Season 3, I feel like there has to be a connection there. It wasn't just like Cat chose Scratch out of the blue [to emulate], but that is still to be decided.

If she's been in prison, how was she so familiar with Scratch? Was Lindsey keeping tabs on him?
Messer:
Yeah, she definitely had contact with the guard that had the ability to be in both prisons and is likely the daddy of her baby, which is also crazy. [Laughs] When [writer] Breen [Frazier] pitched me that, I was like, "That's crazy. We're not doing that." And then it became, "We can do it for an act, but it cannot be real."

That would've jumped the shark.
Messer:
Yeah, it was like, could she be pregnant with Reid's baby? I was like, "No! She could say she is, but she can't be!" It was just funny.

You can argue that this whole experience changed Reid a while ago. The one way he could one-up Shaw (Harold Perrineau) last week was to think like him and injure himself. Does he think what Cat says about him might be true -- not that he enjoyed hurting those inmates but he'll never be the same again even though he says he can "go back"?
Messer:
Yeah, and he says, "watch me." It's us speaking to the reality of that. It's exactly what that character would taunt him with: You crossed a line and can never go back. But even JJ said to Reid, "I would do that. If that was my life on the line and I had to survive, I would do anything it takes." He will, in good conversation, be able to get past that. I don't know what the equivalent would be in real life, other than the basic thing of "people surprise themselves" a few times in their lives. Usually it's along the line of good things, but I do think there was an element of self-survival that he had to embrace, and that meant there were no lines anymore.

He's gotten aggressive, not in a physically imposing way.
Messer:
Yeah, but aggressive because we've never really seen him threatened. So you're seeing him stand up for himself. You're not seeing this kid who has tales of being bullied at 12 years old. He has learned from all of that and it's like, "Not today. I'm done with that. I'm already vulnerable. I'm in a place I shouldn't be, but I'm not going to let you win."

I liked the beat of him last week waiting for the door to open instead of opening it himself.
Messer:
Oh, thanks! I loved that beat. I was like, "We gotta play that." Again, that feels real to me. He's spent all this time locked up and he's not used to the freedom of opening a door. It's just a tiny little moment, but I felt like now was the time to play that, fresh out of jail. Maybe we'll have versions of that next season, but it felt most impactful right after he was released.

How is Reid going to balance taking care of his mom and work now?
Messer:
That will depend on the availability of Jane once again. I would love to see her again like we saw her this year. I think that would be great, so we can see how she's doing and how he's juggling it all. We'll sort of lean into what a lot of people are doing now, where you hit that age in life where you have to be the parent for your parent, especially for anyone suffering a degenerative disease like that. I have some friends who are in that boat and it's a really sad journey because it's not like all of the sudden you have Alzheimer's and you're done. There are really good days within that and really bad days within that. We've been able to see that with his mom this season. I think we'll find a way to find a balance there and I hope Jane is available so we can have that relationship play out onscreen.

Is he going to be fully reinstated in the BAU? He still went to Mexico without telling anyone.
Messer:
We have ideas for what the first episode would be. That question will be answered then. I don't want to say anymore in case that's not what we go with, but we're going to play that. There's a little bit of "you shouldn't have done that," but we want him back on the team. We'd like to get him back on cases as quickly as we can.

Matthew Gray Gubler, Criminal MindsMatthew Gray Gubler, Criminal Minds



Was there any scene that was planned or shot with Reid and Morgan? Morgan saying he was going to bring them breakfast was such a tease.
Messer:
Oh, I know. We didn't shoot it. Shemar guest-starring was not our initial plan, but because he was cast in the pilot for S.W.A.T., which started shooting right when we needed him, we knew we had to get him back now, and we were able to use him for only a day. We wanted him to be upset that he never knew Reid was locked away because Reid didn't want him to know. Otherwise it would've been like, "Wait, Morgan's here. Why didn't we ever see him in the jail scenes?" And it's because he didn't want another person worrying about him and I believe that about Reid.

I talked to Matthew and Shemar about it: Should we do a scene with those two? And the thought was their last scene together was so good last season, and even the no-words-needed nod between them before Morgan walked to the elevator was more powerful than anything we could've done with him bringing him breakfast. It didn't feel like it was worthy. And at that point, the real takeaway for us was Morgan and Garcia because she's had a rough year and almost quit. She said if Reid died she was quitting. She was so honest in her explanation of that. When we write that for Garcia, it's how we all feel and hopefully how some of the audience feels as well: It's been one helluva year and I don't know if I can do this anymore. It's acknowledging how we all feel and how the fans are feeling.

Is Garcia going to be rejuvenated now? Well, most of her team is in danger, but Morgan gave her a pep talk and Reid is OK.
Messer:
I would love to see that reinvigorate her. She's playing a very different relationship with Alvez than we've seen her have with anyone. We'll want to sort of explore that and see if there are opportunities for softness between them. I feel like he's really spent the whole year trying to earn her love and respect and we'll want to push it a little further versus repeating the beats of this year.

Morgan told her to go easier on him so she has to listen to her Chocolate Thunder.
Messer:
Exactly! That was by design! If Morgan says it, she's gotta give it her all. That was sort of the thought process behind it.

Why didn't Garcia hand in her resignation letter on pink stationery? She gave Hotch (Thomas Gibson) her resume on pink stationery.
Messer:
Well, it was in an envelope, so we couldn't see.

That's true.
Messer:
We did not see, but we like to think she did the same thing. I love that you remember these things! But we knew that Prentiss would never look at it. Prentiss wouldn't even consider it, but our thought is that it's on pink stationery.

Prentiss has done some questionable things this season to help Reid. She's like the anti-Hotch, going rogue while he was very by-the-book, which is in line with what we know about her. Is this going to be the way she leads -- willing to go above and beyond for her team?
Messer:
I believe so. When you look at the character and her backstory, living in the gray area of espionage, she definitely knows, "I can get in trouble for this," but if this is going to save my team, then I'll gladly get in trouble for this. I believe Hotch had a bit of that as well, but you're right, less than Prentiss.

Hotch wouldn't have put out a fake AMBER alert about Lindsey.
Messer:
Right. That's a gray area, but she got Ian Doyle by not always playing by the rules, so I feel like she has success in doing what she believes is right as long as it doesn't hurt anyone. I feel like she's bringing all of that from the character's history to her leadership and I love her for it.

Is the plan to completely end the Scratch storyline next year?
Messer:
Well, there's a little bit of math involved in this. We have an order for 22 episodes, which takes us to 299 episodes. Part of me feels like we should leave Scratch around and maybe he's our big baddie for 300 -- fingers crossed we get 300 -- so that's the thought right now, that we have him be part of a milestone. Then again, that could be part of a bigger thing for 300.

I look back on this time back in Season 4 going into Season 5. We didn't know what [Episode] 100 was going to be. We didn't decide that story until we were all back in the room and talking about how we were gonna get Hotch out of this situation with the Reaper. There were all these pitches like, "We do this and that, and at the end we catch him." And I was like, "Or we don't and he's our big baddie in 100 and he does something horrible and changes the lives of our heroes." We knew that was the goal for Episode 100, but we didn't know how that was going to manifest until we got much closer to it. And there was a huge debate in the room if we could kill Haley or not. So I can't say right now that Scratch will be in 300 or the thing that drives us to 300, but I like that he's still out there because Episode 300 is still out there too.

Criminal Minds returns in the fall on CBS.

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