'Blindspot' Creator on Series Finale's Cryptic Ending and Why It Took 3 Months to Film (Exclusive)

Barbara Nitke/NBC/Warner Bros.

'There is no right or wrong. That ending will evolve as you need it to,' EP Martin Gero tells ET about the series' final scene.

Spoiler alert! Do not proceed if you have not watched the series finale of Blindspot.

Did Jane get her happy ending? NBC's Blindspot ended its five-season run with the 100th episode on Thursday, tying up many of the loose ends that had been teased out all series.

Through the hallucinatory side effects of ZIP, Jane (Jaimie Alexander) reunited with several key characters from the past five seasons, from her brother, Roman (Luke Mitchell), and her handler, Oscar (Francois Arnaud), to Reade (Rob Brown) and Borden (Ukweli Roache). Other actors who dropped by included Archie Panjabi (Nas Kamal), Michelle Hurd (Shepherd), David Morse (Hank Crawford), Bill NyeLou Diamond Phillips (Saul Guerrero), among others. They were just a sample of the more than 100 guest stars, from nearly every episode of the previous 99, who returned to take part in the series' final episode. 

Faced with the prospect of total destruction, Jane and Weller (Sullivan Stapleton) successfully diffuse the last bomb, conspicuously located in a trash can in the middle of Times Square -- a callback to the series' opening scene in the first episode. Their final mission complete, Jane, Weller, Patterson (Ashley Johnson), Zapata (Audrey Esparza) and Rich Dotcom (Ennis Esmer) were relieved of their duties -- the next chapter of their lives still unwritten.

It appears they all get fresh starts as the episode flashed forward to a large family gathering with the team happily established in their new lives. But is it too good to be true, as Jane questions in the end? To get the lowdown on Blindspot's final episode, creator Martin Gero breaks down how the series' ambitious swan song came together -- from a three-month shoot featuring over a hundred guest stars to the meaning of Jane's happy(?) ending.

ET: In this final episode, there are a lot of cameos, characters you'd never think you'd see again. How did you pull all that off? 

Martin Gero: There's over 100 guest stars in the [episode]. There are the ones you'll notice, but there are also -- in the background of scenes, especially in Jane's hallucinations -- there is at least one guest star from every one of the previous 99 episodes in the show. So it truly is a Blindspot, this-is-your-life type of episode. We had this idea about a year before we started shooting and the second NBC picked us up, I just got on the phone and called literally a hundred actors, like, "Please come back and do one day. Can you come back and do one day?" And we wrote this episode in the middle of the season so that we could start shooting it.

We shot this episode over three months just to accommodate everyone's availability because typically a TV show shoots for about nine or 10 days. It was going to be impossible to get everyone's availability to line up in that nine- or 10-day window. When Archie Panjabi says, "I can do this day or this day," you're like, "I'll take it. We'll make it work. Just fly to New York. We will rearrange the show schedule around you." That's how we were able to do it. Because we did it over such a long time, to finally see that first cut and see everyone together onscreen, it's really crazy that we were able to pull that off. There's no green screen or split screen. Everyone was actually in the room.

How long did you actually work on this during the script phase because it must have been a bit more challenging than a normal mission-oriented episode of Blindspot?

About halfway through season 4, we were like, "OK, it's time to take these loose cards that we've been keeping for the past five years about what the finale needs to be and start to have a real conversation." Truly one of the things we did was ask, "What is in everyone's dream finale, no limits?" It would be great if Reade and Tasha got married. It would be great if David and Patterson got married. It would be great if Zapata and Patterson got married. We're listing all the things we want. This is a show that plays with reality really well. We already have that language and rule established for our universe. So I was like, "Can we do it all? Can you find a way to do it all?" We knew ZIP was going to play a big part in the last season. So the idea that Jane has a tenuous hold on reality, that would allow us to explore a multiverse of different finales, but without it feeling disparate. It needed to still feel like one piece.

It was a tricky balance, but we have truly some of the best guest stars that I've ever worked with working on this show and a network that was supremely gung-ho to push the envelope and do something that was different. I'm completely stunned that our crew was able pull this off. It was a very, very difficult episode to film, obviously, because it was so hard keeping continuity. Even transitions going from one set to the other in a shot, sometimes those were filmed months apart. And so, just the confidence that we had in our team to do something like this was what allowed us to do it.

Scott McDermott/NBC/Warner Bros.

I did spy your cameo as an officiant during the wedding montage. Did you write yourself in or were you persuaded?

I jumped in there. It was kind of a last-minute [thing]. I've done a cameo on The L.A. Complex, which was my show previous to this, and the show immediately got canceled after I did my cameo. So I took it as a bad omen of "I should not do that. I should not do dumb little Hitchcock things." And then I was like, "Well, we're not going to get canceled probably if I do this." Joe Dinicol, who plays David, we've been very good friends for well over a decade now. He was the officiant at my wedding and I thought it would be a funny life swap if I was the officiant at his wedding to Patterson. 

At the end of the day, Jane and Weller diffuse the last bomb in Times Square and there's a flash-forward to a family gathering where they seemingly get their happy ending. But because it's Blindspot, the question is raised about whether Jane actually died or if the happy ending is all just a mirage. Is she dead? Can you basically set the record straight about what Jane was flashing to in her head? 

(Laughs.) No. Here's the thing. I think we had a very strong idea for what we wanted the end of the show to be. But we also felt like, because it's Blindspot, there was a duality in what we wanted and needed, and what the show wants and needs, and what the fans want and need. We were like, "Is there a way to build this where we believe our intent is very clear, but it is very open to the alternate interpretation?" And to our great surprise, it really becomes a Rorschach test of optimism or pessimism.

About 50 percent of the audience is convinced she's dead and this is all a dream. And 50 percent of the audience is like, she's essentially imagining a version that could have gone wrong and being thankful that it didn't. It's really amazing. Even the cast was 50/50 on what they [believed]. They were like, "I can't believe you kill Jane!" And then they're like, "Oh, she got her happy ending." And I was like, "Wow. OK, it works."

Tasha ends up being a private P.I. Rich has a boyfriend. Rich and Patterson have created a machine to find gold. Kurt and Jane are fostering kids. Were these all the endings you had in mind for these characters?

Yeah. I think we wanted the show to have a finality. We wanted the audience to know, I'm not missing out on adventures. The FBI missions that this TV show was about are no longer going on without me. But the idea that there are a bunch of fun spinoffs happening out in the world, it's a jumping-off point for fan fiction and a jumping-off point for potentially new series down the line. I would watch Rich and Patterson as treasure hunters. I would even watch a family drama with Kurt and Jane. So yeah, just the idea that because this is ending doesn't mean their lives are necessarily. 

Back to the ending, I'm questioning it more. I thought Jane was happy and totally fine. But now, maybe not...

Again, 50 percent and there is no right or wrong. That ending will evolve as you need it to. I think everyone right now needs a win and so everyone's like, "She lives! Thank god."

Is there a finite answer though?

Yes. And, not that this is the type of show that merits it, there are hints in the text throughout the season that make it pretty clear. Even in this episode, [there are things] that make it pretty clear what's going on. But both interpretations are totally valid and are intended to be totally valid.

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