Any given episode of The Leftovers is unlike anything else in TV history, but Sunday’s episode of The Leftovers — the fifth of its eight-episode third and final season — was really unlike anything else in TV history.

“It's a Matt, Matt, Matt, Matt World” continued a Leftovers tradition by throwing aside most of the show’s other characters to follow Christopher Eccleston’s stubborn, self-possessed minister Matt Jamison, a man who’s attempting to square his faith in God with a world where 2 percent of the planet’s population disappeared into thin air, with seemingly little rhyme or reason behind who was taken.

The hour puts Matt aboard a ferry in the middle of the ocean between Tasmania and Australia, struggling valiantly to reach the place where he believes he needs to be when the end of the world arrives. (Don’t ask, because it’s about to get weirder.) Instead, he finds himself on an all-night ride with a bunch of lion-worshiping sex cultists having some sort of wild orgy, then meets a man who died and returned from the dead believing he was God. To say that none of these developments sits well with Matt would be an understatement — but Matt is hiding an even deeper secret.

I talked with Eccleston a few days before the episode’s debut about Matt’s evolution, filming on a boat in Australia during the country’s winter, and what happens when a lion roars right in your face.

Our conversation has been lightly edited for length and clarity.

Todd VanDerWerff

When you first got the script for episode five, talk me through the process of reading that script and being like, "We're going to do that?"

Christopher Eccleston

Unalloyed joy. If you're playing a character called Matt, and the episode's title is "It's a Matt, Matt, Matt, Matt World," you're pretty happy, and you know it's Nicole Kassell [who also directed season two’s Matt-centric episode “No Room at the Inn”] coming back to direct. We developed a very strong working and personal relationship.

Of course, to the viewer and to anybody reading the script cold, everybody's like, "What the fuck is this?" But to me, I've been on The Leftovers for two years, so it made perfect sense. You learn not to be surprised by Damon Lindelof's brain.

Todd VanDerWerff

The show has turned one episode of each season over to you. How have you charted Matt’s journey through that time, especially how he’s grown and changed?

Christopher Eccleston

There isn't much growth between one and two. He's your bone fide religious maniac, isn't he? "I'm right, I'm right, I'm right, I'm right, I'm right." And then it completely pivots in season three. I had a couple of episodes living with the new and enlightened Matt Jamison and that was wonderful. But exploring the varieties of pigheadedness of the religious maniac was very enjoyable, if that makes sense.

He becomes a father in season two, and I think that absolutely opens him up to what happens to him in season three. Becoming a parent is enormous for Matt. He doesn't realize it at the time, but I think he makes his peace with the world and realizes that his contribution to the world has been entirely negative.

If Matt was told to leave one sentence to Noah, his son, in the first or second season, it would be, "Love God." And I think the note at the end of season three would be, "Keep an open mind," and that's a very different Matt.

“As somebody said in season one, Matt is just another asshole who thinks he's God, and then Matt is confronted with an asshole who thinks he's God. That's the thing that tests him most of all.”

Todd VanDerWerff

As you come out of episode five, do you think Matt still has some faith, and it’s just been tempered?

Christopher Eccleston

I don't think it's been tempered. I think his faith has been entirely realigned for the good. His faith is now in humanity, rather than a false idol. I think his faith in a patriarchal or any other gendered idea of God and organized religion has been thankfully demolished. I think that is a beautiful thing, and I hope it happens to every single religious leader breathing on this earth at this moment.

Todd VanDerWerff

This final season began with Matt essentially losing everything. How far down do you think he had to go to have this moment of self-realization?

Christopher Eccleston

The darkest hour is right before the dawn. Yeah, he did have to lose everything. He loses his wife and his son because of this obsession with God. Of course, at that time, he doesn't realize it's a loss, because he thinks they've lost, because they are not on God's path. Ultimately, he realizes he's given up the things that are most precious to him in a hopeless pursuit of certainty.

Todd VanDerWerff

You mentioned his pigheaded aspects earlier. What was exciting about playing a guy who’s so certain he’s right, and the world keeps trying to tell him he’s wrong?

Christopher Eccleston

Our ability as human beings to deny the truth even though it's right in front of us. A character with religious certainty or any other kind of certainty is always going to be a very dramatic character because they are forever hitting obstacles.

If you don't have any hard and fast beliefs or ways of living, you don't hit as many obstacles. You'll hit obstacles, but your way of negotiating them is much more fluid. Matt’s way of negotiating the world is that many, many years ago, he decided that God is the answer.

Todd VanDerWerff

You spend a lot of time with the great actor Bill Camp, who plays David, the man who claims to be God, in this episode, and it results in one of the more devastating scenes of the series. What was both the process of filming that scene and working with Bill like?

“We were out on the water with a lion with lots of naked people, yeah. It all happened. And we got paid for it.”

Christopher Eccleston

I've never laughed so much in my life as in the short period of time I spent with Bill Camp. If me and Bill were not on set being incredibly intense and impassioned, we were just, as we say in Britain, pissing ourselves with laughter.

That was informed partly by the idea that he was playing God and there was a lion and everybody was naked, and mine and Bill's experiences as unemployed actors down the way, and the idiocy and the vanity of actors including ourselves with big storylines and our own lives up until that point. I love that man, and no other actor could have played that role.

It was technically, spiritually very important for me to work with somebody like that because he's at the top of his game, and I learned. It was just a joy to do that episode with him.

Todd VanDerWerff

When you shot this episode, were you actually on a boat?

Christopher Eccleston

Yes, we were. We drove about 25 minutes outside Melbourne, and we hired a ferry for a few days, and we just kept circling. It was night shoots so it was cold. It was winter there. We just kept going round in a circle, and at various times we had plotted a backdrop we needed, and that duly arrived. We were out on the water with a lion with lots of naked people, yeah. It all happened. And we got paid for it. [Laughs.]

Todd VanDerWerff

Did you have questions about the lion, or did you just roll with that aspect of the episode?

Christopher Eccleston

I remember asking the [lion’s caretaker], "Where's the lion from?" And he said, "Brisbane." And I said, "No, where's the lion from?" And he went, "Oh, it's Indian." That was funny.

We had all the safety elements in place, but there is a take, and I'm hoping that it's included in the final cut, where the lion was pretty sleepy and pretty unengaged, but for some reason maybe the lion picked up a lot of adrenaline coming off me and Bill and the very focused concentration of the crew, and he suddenly woke up and roared and I jumped up six inches in the air, and it's on film. It was primal. I felt the primal terror.

Todd VanDerWerff

I’ve never had a lion roar at me. Is that your natural reaction to something like that?

Christopher Eccleston

It was incredible. I was looking at Bill. We were doing something, and only in my peripheral vision did I see it, but I heard it. We all heard it, but I was the asshole in the lion's eye line. You know in cartoons when characters jump in the air and then run in the air? It was a little bit like that. [Laughs.]

Todd VanDerWerff

You’ve shot in different locations every season, but what did moving to Australia this season give you as an actor?

Christopher Eccleston

We had to be embraced by New Yorkers and then Austinites, and they're very different people, as you can imagine. And then be embraced by Aussies and Kiwis because a lot of the crew that work in Australia are from New Zealand too.

It was perfect for the series. I thought it was wonderful, an American show on American television left America. I think that was beautiful for the story and informed the story. An acknowledgement of the wider world in an American television show, I think, was very, very important, adding an international element to this phenomena of a percentage of the population disappearing.

There are differences in working, and they had to be embraced. There are huge differences in working between New York and Austin. We shot the pilot in a heat wave. We had actors fainting. Then we had people fainting from cold in the first season. Then we had people fainting from heat in Austin, the Texan summertime. Then we ended up in Australian winter with a lion. We had to embrace that. It makes the production more difficult, but it also makes it more interesting.

Todd VanDerWerff

You mentioned that you think it was important for an American show to film in another country, and individual countries’ TV industries tend to be a little parochial. What do you think getting out into another country does for a TV show?

Christopher Eccleston

It's the same in the UK. There's nobody more parochial than us, closed-off little islanders.

Everything is to be gained from it in terms of cultural exchange, in terms of location. You cannot go into other people's country and expect to work the way you do in your country. It's like going into somebody's home.

I always say this: We're guests. If they do different shooting hours, we cannot impose. Obviously, there are all kinds of implications for that, politically and culturally and spiritually. It's like the World Cup of football is played in a different country every four years, and that's what makes it a world game, I think. Everything is to be gained from it.

Todd VanDerWerff

There are a lot of things in this episode that push Matt to his breaking point, from the orgy to the lion to the man who says he’s God. Which do you think pushed him the most, or made him the most uncomfortable?

“I think he's angry at God from day one, Matt, but he denies it. He turns the anger into worship.”

Christopher Eccleston

Oh, the God, false idol, Bill Camp. Definitely.

As somebody said in season one, Matt is just another asshole who thinks he's God, and then Matt is confronted with an asshole who thinks he's God. That's the thing that tests him most of all. That enrages him. The other two things are about Matt's prudery, really. That is about Matt's ego.

That's the one. That's the final straw. Fuck the lion. I could deal with lions and nudity, but somebody saying he's God instead of me? I have to deal with that.

Todd VanDerWerff

The relationship between Matt and Nora has been so important to The Leftovers over the years, and you’ll hopefully get some scenes with Carrie Coon in the show’s last few episodes. What has building that relationship been like?

Christopher Eccleston

Amazing. The pilot, she was pretty much unknown outside theater, Carrie. I felt a connection with her. We chatted. I left a book called Stoner, a rediscovered classic by John Williams, an American novel, on the doorstep of the trailer because we talked books. She's a voracious reader.

At the pilot, we weren't brother and sister. That was something we learned when [the show was] picked up. It's been amazing to see. The minute I met her, I thought, "She's extraordinary." I remember the big scene in the pilot where she makes a speech and thinking, "Wow. Who is that?"

She's just exploded, hasn't she? And it couldn't happen to a finer person, really. She comes from the theater, as so many of The Leftovers’ actors do. Bill Camp, Justin Theroux, myself, Ann Dowd, Kevin Carroll, Jovan Adepo. Basically theater people who've paid their dues. Carrie's paid her dues, and now she's having a moment, and it's wonderful to see.

Todd VanDerWerff

This episode ends with the revelation that Matt is dying. How do you see that as you go forward with the character?

Christopher Eccleston

Cancer's always been there in Matt's life and universe, because he first experienced it as a child. He addresses it in his opening speech of episode three, season one. It's always been something that I've had to consider as a motivating factor for Matt in terms of the way he lives his life. I think he's angry at God from day one, Matt, but he denies it. He turns the anger into worship.

It felt right in terms of his relationship with that illness. We don't see it. It's just said. I felt it was done very, very subtly. He knows. Matt knows. I think the clock is ticking for him to become a real human being and become his true self.

The Leftovers airs Sundays on HBO at 9 pm Eastern. Previous episodes are available on HBO Go.