The Hollywood Reporter speaks with the executive producer and host about the surprising person responsible for the latest Boston Rob and Sandra twist — plus, the first one out speaks in a special edition of the 'Series Regular' podcast.

[This story contains spoilers for the season premiere of CBS' Survivor: Island of the Idols.]

Boston Rob Mariano, Sandra Diaz-Twine and their gigantic statue heads rightfully commanded attention throughout the Survivor: Island of the Idols premiere and its preseason buildup. But the two legendary Survivor champions' involvement in the season extends far beyond their home at the titular island — indeed, it stretches all the way to Tribal Council.

In the closing scene of the premiere, "I Vote You Out and That's It," as the losing Lairo tribe walks into the sprawling Tribal Council set for the first time (and for the last time, for ousted poker player Ronnie Bardah), two additional parties join in on the action: Rob and Sandra, sneaking in from offscreen to nestle into a private viewing bungalow. From their top secret perch, the season's two living idols will occupy the best seat in the house to watch the Island of the Idols Tribal Councils, silently observing as host and executive producer Jeff Probst grills the rookie players all season long.

Probst owns the idea of inviting Boston Rob and Sandra back onto Survivor for season 39, serving out their roles as mentors. As executive producer Matt Van Wagenen tells The Hollywood Reporter about the season's origin story: "I was walking back from a rehearsal [during David vs. Goliath] with Jeff, and we were talking about different ideas. He said, 'What if we do something where we took some of our biggest characters and built a Mount Rushmore on a cliffside, carving their faces out of stone?' Truthfully, when he pitched the original idea, it's not so different from what we have going on right now!"

But Rob and Sandra's secret seat at Tribal Council? Probst takes no credit for the idea. Speaking with THR mere minutes after the first elimination of the season, and standing only a few feet away from the seats, Probst reveals the surprising mind behind the covert viewing booth…

…Jimmy Fallon.

The Tonight Show host and Saturday Night Live alum is a noted Survivor fan, whom Probst has credited in the past for coming up with the premise for Survivor: Second Chance, a season in which fans voted players back onto the show. Speaking with THR through email, Fallon says he's constantly pitching Probst on new Survivor twists.

"Jeff probably regrets giving me his email after he was on my show a few years ago," writes Fallon. "I use it all the time. I will have ideas in the middle of the night and just shoot off a short email and say 'Is this anything?' Now and then he'll respond with: 'This email is no longer in use.' But I know he's reading them!"

According to Probst, Fallon's pitch for a top-secret voting booth first landed in his inbox about two or three years ago. "We thought it was a great idea, but we could never make sense of it," he says. "Why would you bring a player back to secretly spy on Tribal? We weren't sure about it. When the [Island of the Idols] idea took flight, we thought this was the time. This is when we can use the secret Jimmy Fallon viewing booth — the Fallon Booth."

From a design standpoint, the so-called "Fallon Booth" is the centerpiece of the season's Tribal set, the point of origin from which dozens of different but similarly designed huts were conceived and built by longtime art department guru Dax Pointon and his team.

"Dax realized, if [the booth] is going to be something that's literally at Tribal Council but nobody can see them, then we have to design the entire Tribal around that viewing booth," says Probst. "Even though you see 40 huts here and 60 fires, it all started with this tiny little six-by-six viewing booth, so everything else could orient around it."

What other Fallon-inspired Survivor twists might we see one day? According to the Tonight Show host himself, the list is potentially quite long, at least as far as what he's dropped into Probst's inbox. For example: "I had one long idea once where the two tribes finally become one only to find Survivor Australia is filming their season on the same island and now those two tribes have to go at it. It's a double season! Or something... I think. Jeff hasn't got back to me on that one." How about Fallon himself on the show as a contestant? "I would do a short overnight 'glamping' version of Survivor. The winner gets to name the tribe. I'd love to see a 'Fallon' tribe."

"I'm just a fan of [Probst] and of Survivor," he says, "so I'm always thinking of new twists and things that don't completely change the game that I love, but enhance it. If it ain't broke…"

For more on the Survivor: Island of the Idols premiere, keep reading THR's conversation with Probst about the first three days of the season, conducted a few short moments after the first Tribal Council's conclusion. Additionally, listen to the latest episode of the Series Regular podcast for a much closer look at Ronnie Bardah, the first one out of Island of the Idols.

These first three days were a lot of fun. You must be feeling good.

I'm feeling really good. Everybody's excited. It's a really big idea. There are so many variables. Then you're done with the first episode, and you feel like everything played and executed well and that the audience is going to like it. The best part is when you're turning the show over to these players — and this season, we're turning over a big part of the show over to two returning players. It's something we've never done. Rob and Sandra were awesome today, straight out of the gate. It's one thing for them to know [what's at stake], but to deliver on it? Not easy. They are basically producing and hosting that moment out there on their own. I'm not out there. No one's out there. It's just them. I was so proud of them, and so impressed.

As we're talking, I'm not sure exactly what happened when Elizabeth met Rob and Sandra. Can you catch me up, as best as you can?

The basic premise of Island of the Idols is you go out there and meet these two mentors, these two experts of the game, Boston Rob and Sandra. They try to teach you a lesson about how to be a better player. Then they're going to give you a chance to test what you've learned in exchange for a shot at an advantage. Today, Elizabeth went out there. Rob showed her how to make fire using flint. Super valuable skill. If you make final four, you better know how to use flint. She was really pumped to get expert guidance. She did a very good job. She learned a lot. She practiced for an hour, then came back, and they said, "Before you go, here's the twist: how confident are you in your fire-making skills?" Rob explained the premise that she could earn an advantage in the form of an immunity idol, good for a couple of Tribals, if she wanted to take him on in a fire-making competition — and if she lost, she would lose her vote. But they proceed to tell her: "Hey, it's the first Tribal. You might not even need your vote!" All of it is a lesson. She took the bet and she lost. She put a valiant effort up, and got a fire going, but she lost. Now she has to go back to her tribe not knowing what's up. Rob and Sandra remind her on the way out: "What are you going to tell everyone? You have to be thinking all the time about the lie." She formulated a lie [about the Island of the Idols], it sounds like it went over well with the tribe, and then we come to Tribal Council tonight, and have a devastating blindside.

Let's talk about Tribal Council. Elaine was at the heart of it, talking about how she believes she's going home — and in the end, she doesn't get a single vote. Vince gets two, but Ronnie gets blasted out of the game. What's your take on tonight?

I think Elaine was in trouble at some point, clearly. She was pretty certain she had heard her name. I don't know why they changed their mind. I don't have the intel on if it was really because they started feeling bad about Elaine. My hunch is it had nothing to do with it. If she was the one to go, they would have cut her tonight, just like they did with Ronnie. I don't think she got out of it because of an emotional sob story. I think it's the game changed and she didn't know it — and Ronnie definitely didn't know it. I feel for Ronnie. You get to know these people through the casting process. He's such a deep thinker and an emotional, nice guy. I don't know what he did at camp that got his game thrown off. I'm guessing it had something to do with a first impression, or people thought he was sketchy, or people thought he was too smart, or people picked up on the poker thing, even though it sounds like he wasn't telling people. I feel bad. It's a weird season, where everyone is so likable, that I think we're going to see some very tough Tribals.

I never would have expected Ronnie to go home first.

I wouldn't have either. I'm curious how this is going to feel on the heels of [Edge of Extinction]. I know there are purists who think there should never be a second chance island. But right now, I'd kind of like to see Ronnie on an island living alone.

"What does he have going on out there?"

Right, in that alternate universe where we have Extinction happening. I'm on the fence about whether we bring Extinction back or not. I'm definitely open to it.

Who impressed you tonight?

Now that I see the blindside, I realize everyone's playing. You never know at the first Tribal. Are these guys cagey or are they just not giving you much? I thought Karishma was great. I like Missy a lot. Chelsea is fantastic. Elizabeth sparks. Elaine is clearly great. Aaron, too. The only guy who was a little cagey was Dean. He'll come out of his shell. We'll get him out of his shell.

He's just too cool for the rest of us!

But I kind of like that! I like his swagger! He'll have to talk a little more at Tribal, but we'll get there.

Do you believe this tribe likes each other as much as they say they do? Do you believe them that tonight was a hard vote?

I do believe it. I don't always believe it. This group, there's something happening, and I don't know if it's just coincidence or if it's tied to where we are in our own society. There does seem to be this layer of compassion that's still underneath the game. The game is going to win — blindsides are going to happen — but I thought tonight's emotion was real. I think had it been Elaine, it would have been very hard. But I think the reason they didn't make it look hard for Ronnie is they couldn't give it up and give it away. But I think people are going back and thinking, "Yeah, we just devastated that guy."

There was a theme on the mat chat at the immunity challenge, where you first met the tribes, and it came up again tonight: how your absence in the first few days impacted their play. They felt it wasn't go time until they saw you. Who knows how much Elaine was being tongue-in-cheek when she said you hurt her feelings by not showing up, but I felt she kind of meant it. What does that say to you?

In the beginning, I thought it was just them being funny: "You weren't there, we're going to flatter you. We need you!" But it's come up so many times that I think it must have something to do with… it's like the theme to Monday night football. You want the theme you're familiar with. What you're familiar with is the guy who gives you the very little information. It probably comes down to the fact that when I show up, I'm the guy who says, "Here's what you can expect." There was no one to say anything. Maybe it felt like a surprise party without a cake. (Laughs.) I don't know! I have not figured it out yet. I think it's mostly centered on lack of information, and that being very unnerving. There's a pace to Survivor: "Jeff shows up on a boat, we know what's happening." Instead, they're left to go, "Wait… it's just us?" I think if we do this a second time, the next group would be like, "Okay, we've seen this before. The dude ain't here. Let's get the game going." It reminds me to continue finding a purpose to change the show. We don't just change it to change it. We change it with a new idea in mind. I think that's a really good lesson for me to remember. Change for the sake of change? I'm not so sure. Change with a sense of purpose? Go for it.

Interviews have been edited and condensed for clarity.

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