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

The BAU has a case of déjà vu in the worst possible way.

After Hotch (Thomas Gibson) gets swatted for allegedly plotting an attack on Wednesday's Season 11 finale of Criminal Minds, the trail leads to Antonia Slade's (Frances Fisher) son Asher (Patrick Bristow) and Mr. Scratch himself, Peter Lewis (Bodhi Elfman), who testified against Hotch, for the frame job. But the real mastermind is Eric Rawdon (Jonathan Camp), an imprisoned anarchist on whom Hotch presented a profile in court and who has desperately been trying to blow up cities for ages. He engineers a prison break, which brings Lewis (Aisha Tyler) face-to-face with Ennis (David L.M. McIntyre) again, but the BAU foils that, as well as Rawdon's minions' bombing attempt.

But just when it seems like it's over, their backyard dinner at Rossi's (Joe Mantegna) gets interrupted: There have been three more prison breaks by Rawdon's partners in three other states. The bomb threats were stopped, but 13 serial killers, including Peter Lewis, are on the loose. "We have to catch him again," Hotch says, "along with 12 other murderers."

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Yup, that's going to be your (still-unannounced) Season 12. Re-catching unsubs might sound redundant, but it's no more redundant than catching a new unsub every week in 42 minutes. While Criminal Minds has done lengthy or even season-long arcs before, this will be the show's first time taking a serialized approach — a refreshing change of pace for a well-oiled machine that would also allow it to mine its deep bench of ol' creepy baddies.

"It was something Breen [Frazier] and I got really excited about," showrunner and executive producer Erica Messer, who co-wrote the episode with Frazier, tells TVGuide.com. "Obviously any time one of our team members is in trouble, it's always fun and dramatic ... but this was a different way to go about it with much different stakes, and it sets up something new and exciting for next year that we've never done before."

So what will next season look like? Who else is in this baker's dozen of unsubs? When will Morgan (Shemar Moore) get replaced? And when will we officially hear about a Season 12 renewal? Messer answers our burning questions below.

I kind of saw the multiple bomb threats coming, but not the serial killer twist, which could give you some fertile ground to work with. When did you first conceive of the idea to have unsubs escape?
Erica Messer:
We had such a good time with Tara Lewis this year and the idea that she gets to do something that we don't get to show very often ... interviewing the killers after we've caught them. So when we met Ennis with her back in Episode 5, we loved that guy so much and we loved that world she gets lost in — [she] even lost her relationship over that kind of thing. We were thinking, is there another way to sort of explore that? Given all the Shemar real estate this year, it wouldn't have done it justice if we had squeezed it into this year, given everything else we had to do. We thought, if we end the season with this prison break, wouldn't it be cool for the team to have a victory — but since the team couldn't be everywhere at once, we learn this happened elsewhere? So it really got conceived as we were breaking the finale more than anything. It was just of interest to us all year, this idea of prison. But we didn't conceive of the Season 12 tease of it until we were in the room breaking the finale.

Did you purposely want to do a cliff-hanger? You haven't done one since Season 5, which is more than half the series ago.
Messer:
I know! We felt like it's time. I'm a sucker for the backyard scenes, as you know. I love those. It was something we talked about in Season 7, when we did the first backyard scene with Will (Josh Stewart) and JJ's (A.J. Cook) wedding and Paget [Brewster] going away. For a minute, we talked about doing a cliff-hanger then, in the traditional sense of, we have this lovely celebration and then they're driving home and someone gets in an accident. We thought, no, let's just end it with the team smiling, knowing this is their last dance with Prentiss. ... This year, it felt like we needed another backyard scene to ground ourselves again, but let's do that thing we talked about years ago, but do the cliff-hanger in a way that it's not physically a team member in jeopardy, but it's the team as a whole thinking, "Oh, my God! It's just begun." After 11 years of fighting bad guys in some way, we have to start over. Now there's 13 of them out there and one of them is Mr. Scratch, who we know is a scary guy. It felt like a really fun launch pad for us to dive into Season 12.

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How far have you plotted this out? What does Season 12 look like right now?
Messer:
It's funny — Breen and I were just working on it yesterday. All the writers are on hiatus until June, but we wanted to get a jumpstart on what we think the shape of the season will be. It's going to be a really fun, different year. I think, creatively, we're both really excited. I feel like with our amazing fan base who watches every week, you can get away with a little more serialized storytelling than when we started the series. We're excited to catch these bad guys all over again. Some we will have known, like Mr. Scratch, and others will be bad guys that maybe some of the team hasn't caught before. That allows us to have some creative license. And of course there will be our case of the week that may or may not be running parallel with catching a guy who escaped. I feel like, going into Season 12, we've had more opportunities for stories than we've had in a really long time.

Have you picked those other 12 unsubs?
Messer:
We have so many to choose from. A lot of it is availability. Right now, no actor's agent is going to commit to them being available for us. We do know that we want Mr. Scratch to be part of Season 12 in some capacity, or at least the idea of Mr. Scratch being out there. Everything else will be the fun of getting the writers together and to say, "If we could bring back anyone in the last 11 years, who would you want it to be?"

Everyone can pick one person.
Messer:
Exactly! Everyone will have a different answer, which will be great. And then we'll go from there. I think it's a fun journey for our fans to be able to go back in time with us and say, "Oh, my God! Remember what that one used to do?" and "How have they changed now that they've been in prison a while?" Or we could say, "Here's an unsub we captured in 2004, before the series started, and create a brand new bad guy." The opportunities feel exciting.

You've revisited unsubs before, like The Fox, to great effect. Do you foresee focusing on each one or maybe just a couple?
Messer:
The Fox [returning] was a great episode. That was [Episode] 99 leading into 100, but he was still in prison. This will be a different road for us. It might not be the top 12 unsubs of all time. We don't know if we're going to dedicate an episode to each one that escaped. We often start our premieres having had the summer go by, so I would like to believe that if we do that that over the summer the team would've caught a couple of them. It does feel like a great challenge for the team. How have [the unsubs] adapted in prison and how does that relate to their survival on the outside? They might lay low for a while, but eventually they will act on their urges. ... I think someone who escaped at the end of [Season] 11, we would capture [them] by the end of 12. That's probably a safe bet. It won't be like we won't catch anyone all season. It would just be maybe picking a nemesis to focus on.

Has Rawdon's motive changed at all now? He wants to blow up cities, but he's been foiled so many times, so he's clearly not very good at this. But he has minions on the outside. He's let out these serial killers, so how does that go with or against his plan?
Messer:
That will all be part of the fun we will dive into in June with the rest of the writers. He will have disciples out there who will want to follow through with his plan. But ultimately he was stopped and all those bad guys in the helicopter were stopped. That ideology without a leader might just be dead, or we might find out he was the disciple of someone else even. We have a few roads we can take with that.

Matthew Gray Gubler, A.J. Cook and Joe Mantegna, Criminal MindsMatthew Gray Gubler, A.J. Cook and Joe Mantegna, Criminal Minds

I liked the subplot of Antonia and Asher, and her ultimately helping the team in a way. Are we going to see more of them?
Messer: I love Frances so much. She's so great. That's something we're talking about — did she escape? How great would that be? Or is she someone we go back to and revisit in prison again? I don't know yet. But I thought she had such great rapport with everyone on the team. It was so cool to watch.

She told them some cold, hard truths two weeks ago. I thought the most interesting was when she told JJ she secretly wants to be the leader. It felt like she was just messing with her, but was that intended to be a proper reading on JJ?
Messer:
I don't think JJ for one second is saying, "I'm as smart as Hotch. I should be the leader." I don't think that's even in her mind. I think she's confident and smart and I think she is a leader in a lot of ways, but I don't think for a second she ever thought what Antonia said about her. Even in the finale, Antonia says, "I know who you are. You took an oath and you're not going to break that. You're not going to let my son die." And to have JJ say, "Well, that was before your son had guns pointed in the same room as my kid." It's that kind of human behavior we study in the unsubs. What's that thing that changed them, that made them break or bend? I thought it was great that JJ was able to say, "Your son's actions changed my view of things today and maybe I would let something bad happen to him now," whereas yesterday, Antonia's right, JJ wouldn't have let anything happen to him. I thought that was a really cool truth that normally we don't explore.

The parent-child theme culminated with Hotch and Jack (Cade Owens). Jack shut him out at the end, which was sad but truthful and a nice juxtaposition to Henry's reaction to seeing JJ. What is their relationship going to be like now?
Messer:
We talked about that at length. There's so much of what Hotch says to JJ in the backyard. Jack doesn't remember a lot of when Haley died and that is such a blessing, but he will never forget someone busting through our front door and pointing a gun at my dad. What Thomas and I were talking about was when Hotch walks into the office, all he wants is to get a hug from Jack. Thomas and I both have kids who are 12 years old now, and it's different. You can't just pick them up like when they're 5 and tell them it's going to be OK. Not that any of it is easy, but it's not that easy anymore to give them a hug. Jack now has a different view on what dad's job is. A hug is not going to make that any better. It feels like there will be opportunities for Hotch to explore what it's like to be raising a pre-teen in this line of work. I don't know how often [Owens can return], but I know that's a through-line we'll be able to play the whole year. Mr. Scratch attacked Hotch last time. Now he's attacked his character. That's going to be an underlying concern for him: Is this going to be another Reaper for me? How do I protect my son and do my job as a father and as an FBI agent? It will throw some complications into it, as it should.

What Breen and I liked about it too, and Thomas as well, is we see Jack dealing with things the way Hotch would. Very stoic. "You know what, you're asking me if I'm OK. I'm going to tell you I'm OK, but we're not talking about it right now." I think Hotch recognizes a little bit, "That's me in him and I don't know if that's a good thing."

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Hotch was specifically targeted. Is anyone else going to be?
Messer:
Not quite like that. Everything is up for grabs right now, but those kinds of things feel premiere- or finale-worthy. Hotch being swatted, for example, and his own words being used against him — we won't go down that road again. With Morgan being in such physical jeopardy this year more than once, it felt like we covered those bases as well, as far as team members being in jeopardy. There are still other big plans for Season 12 that will be really interesting for our heroes to play — the challenges of being in the job for 12 years and things that happen in life that lead you down paths you never thought would come your way.

In happier news, Rossi and Hayden (Sheryl Lee Ralph) are back together. Is second time the charm?
Messer:
I hope so. I think it's so nice for Rossi to truly have that family, not just his work family. We haven't played his Casanova reputation and it feels like he doesn't want her to go. It always felt like she was the one who got away and it feels like they're at a place where they can talk about why that happened. Her example is, "It's the job and it's never going to change" and he says, "But I have." I do believe that. I believe everybody changes, certainly years after doing the same job. We all adapt and we all find our way and find our priorities. Rossi has grown a lot since he and Hayden were first together. And they have a grandchild and it's sort of their chance to both be there as parental figures, not just for Joy and her husband, but for this little boy that now knows both of them.

Reid (Matthew Gray Gubler) mentioned Diana again. Can you finally get Jane Lynch back? She doesn't have a show next season.
Messer:
Oh, my God! I think the stars are aligning! We might actually be able to get her. Fingers crossed! [Reid and Diana] are going on vacation together, so she's clearly doing better, so it'd be great to actually see her. Thomas saw her on a flight a couple weeks ago and texted me, "She's on my flight right now!" I was like, "Tell her we need her for next year!" [Laughs] He said he did. Hopefully we can make it happen. I would love, really more than anything, if we could get her this year. There are so many stories we could tell with Jane. I really am hopeful.

Is there any update on the Morgan replacement front?
Messer:
We'll probably be having discussions in June about what we're doing. We don't want a shrinking cast. We want to have people in the field. Given that we have to go out and catch unsubs of the week and these serial killers out there, it feels like we can't be an agent down this year. We have to be full-steam ahead. I just don't know who that is or what it might be yet.

Do you want it to be a regular cast member or a recurring role like Lewis?
Messer:
I don't know yet. I love Aisha so much. I'm certainly hoping she's back. Any decision with the cast is a really big decision with a lot of people on the phone. I think when the studio, network and creative weigh in, we'll probably want someone who is around all the time. I would argue that we had Aisha 18 episodes this year, we had Shemar in 18 episodes, Matthew was in 19. So as far as I'm concerned, she was a regular presence on our screen. I loved that and I hope we can make that happen again next year. She's so believable. She has a Prentiss energy about her, just really smart.

We've been talking about Season 12 this whole time, but the show has not officially been renewed yet. When do you think you will hear?
Messer:
You and I will probably hear at the same time. They'll let us know right before upfronts, before they announce it to everybody. We will get the courtesy heads-up. There are discussions being had that are above my pay grade, so I don't know when we'll hear, but I can tell you that creatively we're all incredibly excited for Season 12. We're certainly not running out of stories. The older we get, the more invested we are in these heroes and the bad guys they catch every week. I think we've proven with 255 episodes that we have many more stories we can tell. It's more of that kind of thing right now of dotting Is and crossing Ts than anything else. We don't have big negotiations [with the actors] this year or anything like that. We're just waiting patiently.

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