You boss discusses that shocking Joe twist and what it means for the series

Warning: This post contains spoilers from season 4, part 2 of You.

Joe Goldberg thought he found himself in the middle of a complicated whodunnit, only to find out that, once again, he was the killer.

In part 2 of You's fourth season, Penn Badgley's former bookstore manager discovered that Rhys (Ed Speleers), a.k.a. the person he identified as the Eat the Rich killer was... not real. But rather, Rhys is a figment of Joe's imagination. It seems all that killing and head trauma finally led Joe to a psychotic break.

And now, there's no limit to what Joe (and Rhys) can do. EW spoke with You showrunner Sera Gamble about the twist and what it means for (a potential) season 5.

ENTERTAINMENT WEEKLY: What did you all like about having Joe ultimately be the killer?

SERA GAMBLE: We knew it was gonna end up being Joe, which made figuring out the whodunnit 100 percent harder. There [were] a lot of flow charts happening and keeping track of who is where when to make sure your motive and opportunity line up. Along the way, I heard from maybe one or two people who worked on the show who weren't writers who were just like, "You know, it's pretty satisfying, that whodunnit. Are you sure you wanna do this bats--- crazy thing to your season that's gonna completely overshadow it on every level?" [Laughs] It's like a little bit of, "You do know that you're driving the car onto the train tracks, right?" But I'm pretty sure we're gonna be able to drive straight through to safety. I'm pretty sure we won't get hit by the train. It's fine.

Sometimes the best twist is the obvious answer.

Doing twists and reveals and being able to surprise the audience, some of that is really necessary for this show. But it's not really possible to completely hide the ball when you also are trying to play fair with your story. So what all of that adds up to is that you have to embrace the fact that this is just one part of your job and the most important part is not just to shock you so badly that you fall off the couch when you see that it's Joe. But it's more about how the story really starts at that moment. Now we're into the WTF of it all and that's the part that's gonna be satisfying. It's understanding why it's been happening.

What went into the decision to have him finally fully break?

It's not really a show about how somebody does what Joe does and gets caught. It's more about how we've been watching movies where people more or less do what Joe does for the most part, and they're on the poster for the romantic comedy. He's unhinged when you meet him, but he gets more so as you follow him through the story. And so we've been lucky enough to tell the story of this guy for four solid seasons and he's had devastating traumas in that time, not to mention head injuries. [Laughs] We were like, "He starts a bit crazy. I think we should let him get crazier and crazier and see how crazy he can get and still be a guy you would meet in a bookstore and really trust his recommendations and ask him to watch your laptop while you go to the bathroom."

There is the fakeout when he jumps off the bridge. For a second, I seriously wondered if you all were killing him. Did you consider it?

One of the goals when you're writing a show that has a lot of life-or-death danger is to convincingly tell a story where the audience does not really believe anyone is safe. So that's great that you were thinking that. We've been trying to be just unpredictable enough that you get upset when he falls into the water, you know? Cause anything could happen. Sarcastically, before we ever even cast the show, we said, "If a love interest comes along and works a lot better, the show could just left turn." But then as soon as we shot episode 1 with Penn, it was so clear. The show is Joe's story. What we're making is a show that tracks the arc of a character from beginning to end.

So is he essentially unleashed going into season 5?

Yeah. He has, in some ways, really gotten out of his own way. You see that in his last scene with Nadia [Amy-Leigh Hickman]. The thing that's to me the most chilling is that that doesn't mean that his feelings have all been cut off or that he's no longer a person who cares. He's still both. This was Rhys' pitch to him, was really that he's been working at half-power basically this whole time with the fact that he still holds the idea of romantic love in such high esteem. Love and mentorship are so important to him. That's really the double-edged sword that still remains. He's not like the Superman of killers where he has no Achilles heel. If only he didn't believe in love so desperately, he could just do this forever. And I would definitely be convinced he'd live to 100, but I'm not so sure because he wants to be the perfect boyfriend. [Laughs]

Do you know how this show ends?

We have some ideas that we've been talking about pretty much from the beginning. The thing that we have the most is an ongoing debate. Certainly [executive producer] Greg [Berlanti] and I have talked with Penn about like, this is something we're envisioning for the end, but it's really the debate about what kind of justice would be fair and appropriate for a guy like Joe. And then do we believe that he would get that kind of punishment? My short answer is like, maybe not from the American system. But there might be other ways. [Laughs] So that's the stuff we're talking about.

I won't ask if she'll be back, but I'll put it this way: Was it a purposeful choice to leave Marienne (Tati Gabrielle) alive?

Yes. Anytime someone is still out there, it's both a threat to Joe and also a continuing threat to them. I'll just be honest with you, it's rare but sometimes we get to give somebody a happy ending, at least for now. [Laughs] Marienne was a character we just didn't wanna tear to shreds at the end of the day. She had been through so much by the time we met her. She was the character who kind of broke Joe's brain because she has so much integrity. So we figured that was a worthy pursuit to bend ourselves into crazy shapes, to figure out a way to get her out of the season alive. [Laughs]

You season 4 is streaming now on Netflix.

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