Interview: ‘Star Trek: Discovery’ Writer Carlos Cisco On Unmasking The Breen And Revisiting The ISS Enterprise

The fifth episode (“Mirrors“) of season 5 of Star Trek: Discovery was co-written by Carlos Cisco, working with Johanna Lee. Cisco joined Discovery in season 3 as a writers’ assistant, moved up to staff writer during season 4, and is now a writer and story editor in season 5.

In our SPOILERS interview, TrekMovie had a chance to talk to Cisco about getting a chance to expand on some big pieces of Trek lore in “Mirrors” and more.

Can you give a bit of background on your fandom and how you came to work on Discovery?

I am a huge fan now, but I wasn’t always that way because I didn’t have TV growing up in the ’90s. I had seen some of the original movies, a handful of Next Gen episodes and the J.J. Abrams movies before coming onto Discovery. It was intimidating because didn’t know the franchise really well but I love sci-fi and genre. Once I started on season 3, I began to watch Next Gen episodes and when it became clear we were dealing with Andorians and Orions, our then-staff writer Brandon Schultz suggested I watch Enterprise because that is when they were the most featured and I really came to appreciate it. I had been a huge fan of Jeffrey Combs before any knowledge of Trek, and to find how deep he was in Trek was a delightful surprise. So I watched Enterprise all the way through, I watched all of Next Gen, DS9, TOS, I got up to season 4 of Voyager

So you did an almost complete binge of the franchise during your first year as a writers’ assistant?

Yeah, I was watching like two to four episodes a day. It was a lot. I am an extremely online person and understand how fandoms work and understand that Trek is the fandom that created the sort of framework for all modern fandom. I also love researching things. I love fake histories of and diving into the lore of something. So yeah, I went through all of it and eventually finished up Voyager during the pandemic and kept on, I am current with all the Trek shows.

Was this just extra obsessiveness because it was your job, or because you were you getting into it?

I really enjoyed Next Generation. Deep Space Nine is among my favorite TV series of all time and the one I go back and rewatch the most because it’s just that good, I love it. I will go back to other ones like if we are referencing it in the room.

Carlos Cisco beamed to the set of Star Trek: Discovery

So having watched it all so recently, did you find yourself as one of the quasi-experts in the room?

Yeah. I would have upper level writers texting me asking like, “What’s something I can inject in here?” Yeah, I became one of the experts in the room. I feel like the most passionate people about a religion are the recent converts, and that became one of my positions in the room. So I was always trying to push how could we recontextualize Trek canon for the 32nd century? How can we better worldbuild each season? That was something that was important to me.

For an episode like “Mirrors,” it must occur to you that you are about to double the page on Memory Alpha for the Breen and also the Kelleruns and even the Mirror Universe. Do you find that exciting or terrifying?

Both. Trek fans, they know their shit. It’s a really terrifying and great responsibility to get to be that additive to canon. The Breen were one of my strongest pushes for the season. Early on a couple of us who were really into the lore were asked for ideas on the season big bads and [staff writer] Eric [Robbins] was pushing for the Vidiians and I was like we should do the Breen.” Because, A: They’re not going to have horrible makeup, and B: We can just put a bunch of big guys in suits and they don’t need to talk. Being mindful of the COVID protocols, the suits and masks would be really great. And then there were all the possibilities for the Breen because in every season Discovery is trying to do something we have never seen before. And getting to unmask the Breen was a really big privilege.

“Mirrors” showed how there was more to just unmasking them with the two faces. Can you talk about the look and inspiration behind that?

I don’t remember where in the process we landed on “gelatinous” but when we hit the art team with that they came back to us with deep sea fish like the Barreleye Fish with a see-through head. We got really excited about that. So we started talking about what is this species? Why do they wear the suits? So, the thing we landed on is they have this soft gelatinous form and also a hardened form. Our thinking was that the Breen came up on a very harsh planet with a harsh environment. So they developed a way to protect themselves which was hardening their outer shell into basically a skin, but that takes an immense amount of concentration and energy, making them slower, more sluggish, less intelligent, basically. Over time, they compensated for that by creating the refrigeration suits. Then culturally, it became anathema for them to display that solid face, especially to outsiders, because it was essentially a sign of weakness.

L’ak in his gelatinous state

This idea of a taboo reminded me of episodes like “The Outcast.” So L’ak is part of a segment of Breen society that chose to go against this norm?

Yeah, I think that the Breen that would do that would be outcasts in their society. We still wanted to leave a lot of mystery with the Breen. One of the most appealing parts of being a writer in Trek, is you can see something that was mentioned once in Trek and go, “I’m going to build a whole episode about this, or a whole character arc that explores this.” The Breen started as a single line in TNG and then got one of the most important arcs in DS9. Getting to build and expand off that of that was really cool.

One quick question: Is this the same Breen ship we saw next to the destroyed Federation HQ in the future in the time travel episode?

Yep, that big honking thing next to Federation HQ is the Breen ship. It’s not a space station, it’s a ship. That was one of the things I was super proud of pitching. I had been looking at Breen ship designs, including the Star Trek Online ones, which were these colossal, city ships that could house entire armies and fleets inside of them. And again, talking about what haven’t we seen and what could we have as our adversary. Like, Osyraa’s ship was big in comparison to Discovery, but we wanted to do something – this thing was just a behemoth. Like a Discovery-sized ship could fly into its shuttle bay.

Breen ship

Using the ISS Enterprise was a way to sort of visit the Mirror Universe again. What came first: a creative way of using the available Strange New Worlds set in Toronto, or the decision to revisit the Mirror Universe?

We were given access the sets so we could pitch ideas that could take place on those sets, whether it is the Enterprise or not. There were a few pitches, like one with an old science vessel from the 23rd century stuck inside a planet of liquid mercury. And one pitch was it was a Mirror Universe ship sort of trapped like a ship in a bottle, which became the pocket of dimensional space. We even considered fluidic space, trying to bring in one more little reference [laughs]. So once it was settled to do the Mirror ship, the opportunity to define what happened to the ISS Enterprise after the events of “Mirror, Mirror” was really cool.

Was there any talk about also bringing in some Mirror characters?

We had considered Ethan [Peck] as Mirror Spock early on but there might have been availability issues, I don’t know.

Burnham and Book on the ISS Enterprise bridge

So you say you are the lore guy, so how about a nitpick speed round? Starting with: The Breen aren’t supposed to bleed, right?

They don’t have a circulatory system, it’s just the jelly spilling out. I know they don’t bleed! Come on. [laughs]

The solution to open the wormhole was to replace the photon torpedoes with antimatter, but aren’t photon torpedoes anti-matter torpedoes?

I think they were adding more, okay? [laughs]

Final sort of nitpick: Owo and Detmer were tasked with taking the ship back to HQ, but the warp drive was disabled.  We don’t see it go to warp, so are they not going to show up at HQ for years?

In my headcanon, they are being met by a Federation tug, the 32nd century version of the California-class like the Cerritos. They are heading off to meet them and it will tug them to spacedock. [laughs]

ISS Enterprise leaves for Starfleet HQ

We have talked a lot about lore, but season 3 was a way for the show to kind of jump past all of Star Trek canon. Now in season 5, it feels like the show is reembracing the lore, is that by design?

Yeah, I think the studio and Secret Hideout, [co-showrunners] Alex [Kurtzman] and Michelle [Paradise] all wanted this season to sort of connect Discovery back to the greater body of Trek a little more. That didn’t mean we had to really dig into canon, but there was a greater desire to see what we are familiar with from the past and what it looks like in 32nd century and how it’s different or how it’s not different, and why. Obviously, this is a season that has focused on an episode from the 24th century [TNG “The Chase”] and so naturally because of that, every episode focused on the clues is going to be focused on the whims of a 24th-century scientist. So that is naturally going to have more connections back to what people would consider classic Trek.

Discovery is ending and the writers room wrapped up a while ago. Are you hoping to return to the franchise? If there is a second season of Academy, are you hoping to get back to the 32nd century?

I’d love to, if they’d have me. But if this is the last episode I get to write of Star Trek, I’m very proud that this is my final contribution. I’m hoping to pitch some games to the franchise and stuff like that as well down the line. I’m a game designer on the other side of my career. But yeah, I would love to come back and write for Trek, anytime. We’ll see if that happens.

Finally, last year you played a big part in organizing for the WGA strike, which included rallying Trek writers. Can you talk about that?

Yeah, one of the proudest things I’ve contributed to the franchise didn’t even take place while I was employed on Star Trek. Or [employed] at all. I was a lot coordinator and strike captain. Followers of the strike might remember we did theme days to boost morale and turnout. I, along with fellow captain and Strange New Worlds writer Bill Wolkoff was one of the architects of the Star Trek strike day in May. It was one of the first theme days, and we didn’t advertise. But the turnout from franchise was immense. We had actors, writers, and designers from every single Trek TV show attend. It was, as a fan and a writer, an immensely emotional day and an incredible few hours where folks who worked on the show could fan out on other folks whose shoulders we stand on. There were reunions that hadn’t happened in years and it was a really joyful celebration of the shows we all put our blood, sweat, and tears into.

Carlos Cisco (highlighted) at Star Trek-themed picket day in May 2023 (Photo: JW Hendricks)

The fifth and final season of Discovery debuted with two episodes on Thursday, April 4 exclusively on Paramount+ in the U.S., the UK, Switzerland, South Korea, Latin America, Germany, France, Italy, Australia, and Austria. Discovery also premiered on April 4 on Paramount+ in Canada and will be broadcast on Bell Media’s CTV Sci-Fi Channel in Canada. The rest of the 10-episode final season is available to stream weekly on Thursdays. Season 5 debuted on SkyShowtime in select European countries on April 5.

Note: The interview has been edited for brevity and clarity.  

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I’m not sure I like the reveal. To me, this is one of those things like the Klingon headridges where I think the mystery was more interesting than the answer they came up with. I so wish Enterprise had not explained the headridges and Worf’s “we don’t discuss it with outsiders” joke in DS9’s “Trials and Tribbleations” was the end-all be-all for it.

Also, the behind-the-scenes thinking and explanation for the Breen doesn’t fit with DS9.

Their idea that the Breen come from a harsh planet and harsh environment is directly conflicted in dialogue by Weyoun, who states the environment of the Breen homeworld is actually normal. In DS9, it gave the Breen a mysterious quality that I think made them stand out.

Good point. Pretty much everything about this episode was badly done.

Frankly, given what a disappointment Discovery seasons 3-5 have been, I truly hope Carlos Cisco and Johanna Lee are not invited back. They just aren’t good writers.

as all Disco writers are…

You dislike all the writers on all current trek shows. Not actually sure what you consider a “good” writer.

Just to be sure, it would be nice if we can put all Disco writers in one big box and ship them to Antartica.

DS9 built up a real mystique about the Breen. To find out that they are really green jello people was a bit anti-climatic.


In fairness, though, what would have been exciting enough as an answer to the mystery? Some things are better left unanswered. It brings to mind Steven Moffat teasing a reveal of The Doctor’s (as in Doctor Who) name, abut then admitting he never would. To parapgrase, he said, “What could it possibly turn out to be? Keith?”

In fairness, though, what would have been exciting enough as an answer to the mystery? 

I think you answered the question well in suggesting that maybe the Breen should have remained a mystery.

but on the other hand, who trusts anything Weyoun says?

The Typhon Pact books dug into the Breen in an interesting way, and this doesn’t stray too far from that (in some respects) which is refreshing to see.

Two unnecessary reveals in one episode.


Anyone who says DS9 is their favorite show is already alright in my book!

However I did have a lot of problems with this episode. The whole MU connection and it also being the Enterprise just felt beyond a stretch and very unnecessary. And he confirmed what I think a lot of us assumed and that they were able to use the Enterprise sets and just came up with a story around it instead of the opposite and came up with a story first that warranted it. I really wish it was just another Constitution class ship from the prime universe instead of the ham fisted stuff they came up with that added really nothing to the story.

As for the Breen I do like they are using them again since this is a species many fans wanted to see again. I’m torn with the head reveal but OK with it. But would’ve been fine if they didn’t show them.

I also like the idea of using the Vidians too although IIRC weren’t they already cured by the end of Voyager? But this is why it’s fun to go so forward in the future because now you can use species from any part of the galaxy.

And I suspect we will see a lot more of them in the Academy show.

Agreed on all fronts.

agree on everything ;)

Yep Jason Alexander cured the Phage.

Yeah, I don’t think every mystery or open question needs to be answered by our franchises. I don’t understand the compulsion to answer every open question from past series or movies.

Things like the Breen and Bobba Fett were cooler with less said.

yes. for sure. let the secrets be secrets, don’t explain them, create new ones!

The shame of it all, though, is that this just wasn’t a good episode. It was badly written, L’ak and Moll were really boring, and the Breen’s other face was cheesy-looking. This may have been the worst episode of DISCO since the ship left the 23rd century. What a disappointment this season has turned out to be; after two really fun opening episodes, it’s gone downhill fast and has turned into the same padded schlock that was seasons three and four.

You literally complained about the first two episodes when they aired and now you are saying that were great? And you’re making sweeping judgements about a season being disappointing even though you haven’t seen it all? There’s a word for this: trolling.

That’s nonsense, and you know it. I don’t know why you have a bug up your butt about me, but if you don’t like my posts, stop replying to them. I’m clearly not a troll. I’ve been an active member of this group for years.

Also, I just looked up my comments about the early episodes on this board.

Episode 1: “Now THAT was good.”

Episode 2: I made no comment at all.

Episode 3: “Oh, boy. After two stellar episodes, this was one of the worst in the show’s history. If this is setting the tone for the rest of the season, I’m frankly worried.”

So, M1701, when exactly did I “literally complain about the first two episodes when they aired?” It’s pretty clear which one of us is the troll. So get off my back. You don’t out-rank me and you don’t have pointed ears.

I don’t know. I thought it was a very good episode. The pacing was great. I like the added backstory to Moll and L’ak. I found it added depth and meaning to their characters. And I did love that the MU ship was the Enterprise. As a long-time fan of Trek and loving “Mirror, Mirror” – I often wondered what happened to the ISS-E. This was quite satisfying to me to know where she ended up.
Being a writer myself (I wrote several episodes or ARE YOU AFRAID OF THE DARK and other series from time to time), I quite enjoyed the story telling here and in this season.
I work more in the technical field now but I still write from time to time. Funny enough, I did write a fan fiction years and years ago that find the ISS-E in the future with Mirror Spock at the helm.

Oh neat I used to watch AYOTD when I was a kid good show.

This awful story is what you get when you assign a novice to write this episode. No offense to Carlos Cisco, but the ‘Mirrors’ episode is a huge mess.

The ‘no offense’ made a huge difference indeed… LOL

What they should’ve done with the extra pages they got in the end (to wrap up the series) is go back and ‘fix’ certain things they would’ve done, had they known it was their last episode. Like bringing in Ethan for at least a cameo or recorded log scene and Lorca in the previous one. Would’ve fixed the ‘talk in stead of show’ issues.

Guess we can add the Breen to the list of things the First Splinter did better (a list that already includes the MU).

I still hate the 32rd century, the entire thing completely destroys world building in the Star Trek Universe to me.

If it was the late 25th century or early 26th century, just a difference in Number really, the jump in tech capabilities would be entirely reasonable and no more than from the late 23rd to the late 24th century.
All of the things that happened in the meantime, the burn, the reunification of vulcan etc would have all been much more plausible in a shorter period of time and honestly opening the possibility for many more interesting stories to tell. Even the federation continuing on as a shadow of its former self, the way it is presented in the show, would make much more sense if the burn had been just, say, 30 years ago – and not over 100!

Look at how our real world changed just within the last 80 years since WW2, how a society such as Korea could evolve into two completely different cultures, how entire populations were displaced in Europe, yet that reality became totally normal now.
In star trek, on the other hand, somehow progress and change completely ground to a crawl, apparently, following the 2400s.

Again, that baffling decision completely destroys world building and plausibility of the events in Disco for me. Such a minor thing as the number of the date has have such profound ramnifications towards the plausibility of the story (which was probably only chose because it was beyond ANY mentioned events in Canon) and it is just so disappointing that this decision has been apparently been made on a whim.

And now they are doubling down with SF Academy.
Just leave it in peace and call it an “alternate Timeline/split timeline” or whatever.

This. I just can’t even bring myself to watch Disco anymore (stopped after season 2). Have seen every episode of every other series excluding Prodigy (am getting to that one), but Disco just doesn’t feel like the same universe, and I’m simply not interested.

This episode was damn fantastic and I find Trekmovie’s comments section for this article a bit more wearying than most.

Ah, thank you. The comments here are becoming grumpy central. I liked the episode and this interview was honest and fun.

I love the Trekmovie podcast and the news coverage, but nowadays I do kind of see the Trekmovie comments as obnoxious haters looking for shallow excuses to flex what they think is their creative writing muscle vs. the comments at Trekcore that are a little more down-to-earth and rational. The comments over there are also much more discussion-based as opposed to the reaction-based dramaticism of the jerks over here. I want to be clear, I’m just talking about the comments. Anthony and Laurie’s podcast and this site’s news coverage is one of the shining lights of the fandom in general. It’s just that the comments section make my eyes roll so hard they occasionally fall out.

A. It’s just people giving their opinions. I don’t think people are trying to be ‘haters’ just honest. Yes people are passionate.

B. It’s literally been like this here since 2009. It’s actually better today than a decade ago after STID came out. That was brutal lol.

I liked that TNG mostly didn’t revisit TOS aliens (but when it did, it overused them – see: Klingons — or made them lame – see: Vulcans and Romulans).

I wish Discovery had tried to do its own thing.

Honestly I think it is Enterprise that made the Vulcans lame. Outside of Spock and Sarek we didn’t really even get many Vulcans in TNG

I agree to an extent. That being said I’d rather use an established adversary than invent something new out of whole cloth.

I for one am happy to see the Breen back as they were one of my favorite parts of DS9. I wouldn’t have shown their faces but I like what we got. Im also glad we’re using and expanding on something established as opposed to inventing something brand new. I hope we see the Tholians too as they were name dropped earlier in the season.

Cisco is clearly a fan but it feels like the writers this season really want to be doing an early 24th/25th century show. The story and ideas do not feel they inspired by and coming organically from the shows characters and setting. The show is increasingly contrived as a grab bag of 24th/25th century ideas are brute-forced into Discovey at the expense of its own already weak characters.

They’ve fallen into a catch-22 where the show is entirely dependent of references/callbacks to keep you invested because of its own weak setting and characters…but they’re weak because their development has been sacrified in favor of more refences. The show started started off with training wheels and instead of letting it eventually ride on its own they just keep adding more training wheels.

It’s a shame because in a vaccum I actually think a lot of the Breen development is pretty neat. I hope Cisco, Lee, and others are new and better opportunities with the franchise in the future. But I’m increasingly worried that with Kurtzman in charge it’ll just be more of the same. Coming Soon: 32nd Starfleet Academy! Featuring such instructors as The Doctor, Guinan, Wesley Crusher, and a Soong Android!