The ending of 'Heretic' is intense — and ambiguous. The filmmakers break down the twist, that final shot, and Hugh Grant's Jar Jar Binks impression.

• "Heretic," Scott Beck and Bryan Woods' new A24 horror movie, has an ambiguous ending.
• Hugh Grant stars as creepy Englishman Mr. Reed, who claims he's discovered the "one true religion."
• Sophie Thatcher and Chloe East play Mormon missionaries who become trapped by Reed.

Is there a god? Is there an afterlife? What happens when we die? These are some of the lofty questions at the heart of "Heretic."

The A24 movie, written and directed by filmmakers Scott Beck and Bryan Woods, leans on psychological horror and existential dread for its scares. It centers on Sister Paxton ("The Fabelmans" breakout Chloe East) and Sister Barnes ("Yellowjackets" star Sophie Thatcher), two young Mormon missionaries in Colorado who visit the home of a strange Englishman named Mr. Reed to preach their religion.

Not only do they not win over a new convert to the Church of Latter-day Saints, Barnes and Paxton find themselves trapped in a hellish nightmare when Reed challenges them on their faith and the nature of belief.

Beck and Woods, the writing duo behind "A Quiet Place," spent years researching to craft the "Heretic" script, which is driven more by dialogue than action. It was an aspect of the non-traditional horror film that spooked some major studios — but not A24.

"There were some larger studios that were very interested in making the movie, but they were interested in the more thriller aspects, like the cat and mouse aspects, and wanted to thread out some of the more theological debates, which is what to us was the heartbeat of this film," Beck said.

The filmmakers knew A24 would be a "sweet spot" for their movie, even when writing it. "They're not afraid to hold back on the stories that they're telling or trust the audience, to present movies that can provoke," Beck said of the indie studio. "A24 saw the script and they totally got behind it."

Here's what happens at the end of "Heretic," what Beck and Woods say about the ambiguous final moments, and how Hugh Grant came to star in the film.

Warning: Major spoilers ahead for "Heretic."

'Heretic' ending, explained

When Sister Barnes and Sister Paxton initially arrive at Mr. Reed's house, they're hesitant to enter because the female missionaries are not able to come inside without another woman present. But they agree once he tells them his wife is just in the kitchen making blueberry pie.

After an increasingly uncomfortable discussion about the Mormon faith and religion generally, Sister Barnes and Sister Paxton realize that Reed's claim about his wife was a lie all along. Upon finding that the front door locked behind them as soon as they came in, they realize they need to confront Reed to get out. They venture further into the house to find him in his study, where he reveals his true intentions: to trap them there in a twisted cat-and-mouse game.

Reed rants about all existing religions being derivatives of one another and claims that, through exhaustive studying, he's discovered the one true religion. He offers the young women two doors, one labeled "Belief" and one "Disbelief." But when a defiant Sister Barnes convinces Sister Paxton to enter the "Belief" door, they find both doors lead to his basement dungeon. While alone, Barnes hands Paxton a letter opener, instructing her to stab Reed when Barnes signals her, knowing that he would never suspect a more timid woman to attack him.

Reed produces a decrepit, sickly woman who he calls a prophet. He has the prophet eat a poisoned pie, and she dies, telling Barnes and Paxton that they'll momentarily witness her resurrection, at which point she'll recount what she's seen in the afterlife. While the two young women are distracted trying, to no avail, to get the attention of a Mormon elder arriving at Reed's house looking for them, the prophet seemingly resurrects and describes the afterlife before saying, "It's not real."

Barnes, however, refuses to believe the prophet really entered the afterlife and instead says her description of it sounded more like a near-death experience that Barnes herself had once had. She gives Paxton the signal to stab Reed, but he slashes Barnes's throat before Paxton has the chance to do anything. He then removes a small metal rod from seemingly dead Barnes's arm, claiming to Paxton that this is a microchip and that their world is truly a simulation — hence the prophet's "It's not real."

Paxton counters that it's a birth-control implant and realizes that Reed's lame simulation claim is just him scrambling to recover control. The prophet telling the girls "It's not real" was actually her going off-script trying to warn them that Reed's supposed "resurrection" trick was a ruse, not an indication that they live in a simulation.

Paxton theorizes that Reed switched out the dead body of the prophet with a second woman while she and Barnes were distracted to make it appear she had resurrected. It turns out she's right — Reed invites her into an underground tunnel so she can test her theory, and she does indeed find the body of the first woman who ate the poisoned pie. Reed urges Paxton onward down the tunnel's path, promising that it'll lead to her discovering the "one true religion" he says he's found.

Paxton finds a room filled with caged women. All of them are emaciated and have clearly been there for a while — past victims of Reed's sinister game. In a confrontation with Reed, he reveals he allowed her to find the women because he was able to predict her moves, just as he'd predicted the moves of his past victims, and used their faith to control them.

She deduces the whole point of this game: for Reed to "break" Barnes and Paxton's faith by proving that the root of every religion is simply a desire for control and that none of it is real.

She attacks Reed with the letter opener in an attempt to escape, but he stabs her, too. As they're both bleeding, she prays, much to Reed's annoyance. Before he can finish her off, Barnes (who was apparently still alive but in critical condition) springs up and kills Reed with a plank of wood before finally dying herself.

A traumatized and bloody Paxton manages to escape out the dungeon window and get outside, where she sees a butterfly land on her hand. This is a callback to a moment early in the film, where Paxton tells Reed and Barnes that she wishes to be reincarnated as a butterfly that would land in the hands of her loved ones.

An obvious interpretation here is that Barnes is signaling to Paxton that she's reached the afterlife by doing precisely as Paxton said. However, that's complicated by the actual final shot of the movie: Paxton staring at her empty hand, suggesting there was never a butterfly there at all and that she merely imagined it.

The ending of 'Heretic' has multiple possible interpretations, and they're all valid

The ending is a bit up to interpretation. What are some of the most interesting theories you've heard from people who talk to you about it?

Scott: I mean, we've heard them all from people taking it at face value, or that maybe this is all really was a simulation, or that maybe the characters aren't really physically there at the end of the film.

And what's great about it is those are all layered there to be intentional and totally valid. It's something that I think mimics the heart of the film.

Everybody kind of intuits their own relationship to faith or atheism or existentialism and the big question of what happens when we die. These are the biggest questions that we all have in life, and there's no definitive tangible answer. But the pursuit of those answers is something that interests us greatly, and I think that's the heart of the film.

Bryan: And the lack of pursuit — the idea of certainty, the idea of knowing for sure that you're right and everyone else wrong — is potentially dangerous. The movie's talking about that as well.

I loved the butterfly moment. Was the butterfly really there?

Scott: That's the big question, and we have no answers for that necessarily, that we want to impose on anybody else's perception.

Did you want the audience to walk away with a specific feeling from the film?

Bryan: This is going to sound contradictory, but we do want the audience to walk away with a very specific feeling about the film. But that doesn't necessarily mean that one person's specific feeling about the film is the same as somebody else's specific feeling about the film.

We want people to think about the ending, basically the last 15 minutes and the final moments, and how it all connects to them and how does that intersect with their personal beliefs or disbeliefs. And more than anything, we hope it's a conversation. We hope people kind of talk about it on the way out, and then best case scenario, they see the movie a second or third time and maybe that validates their interpretation or maybe it dismantles their interpretation and they see something new that they didn't see before.

How Hugh Grant became Mr. Reed

How did Hugh Grant come aboard initially?

Bryan Woods: We kind of did the whole full-court press to try to get him. We called up our agents at CAA, we asked everyone at A24 to please help get this material to Hugh and please vouch for this project and it has to be him, is what we kept telling people. It has to be him. It can't be anybody else. It's Hugh or nothing.

He finally read the script and we met with him over Zoom and felt each other out to see if it would be a good collaboration. And then we proceeded to spend the next four months trading emails about the script and the character.

Hugh went really deep on his research, and he wanted to create a full backstory for Mr. Reed. The lengths he went to to do a great job were unlike anything we've ever seen before with an actor.

Did you ever consider delving more into Mr. Reed's backstory within the movie itself? His precise motivations for why he's doing all this are pretty mysterious, and there's no sense of what he was doing before becoming a religion-obsessed kidnapper.

Scott: There's a degree to which the backstory does exist in scripts like this, but we're less interested in putting all of that on the screen. Mr. Reed, to us, is at his best when he's a bit of an enigma, when he's mysterious, and we kind of felt like that's the entry point for the characters of Sister Paxton and Sister Barnes. They're going door to door, they're meeting people at face value. That's how they meet Mr. Reed and interact with him.

There are little layers and touches that either were in the script or that Hugh really brought to life that suggest something about who Mr. Reed might be beyond this day's events. But we love provoking questions more than we like giving definitive answers in many of our films.

Did Hugh go off-book on anything?

Bryan: Hugh was extremely reverential with the script and we really appreciated that. He wanted to make sure that he knew where all the humor was, knew where all the scares were. That was a big part of his homework, making sure he had it down.

But then there are moments where he has these kind of brilliant little ad-libs. One of the ones that comes to mind is Hugh meowing when he's talking about his favorite Monopoly piece or when he's talking about having his wife bring in pie, and out of nowhere he screams "Pie!"

He added these wonderful little things because they're so in character. He's done so much research and he knows the script inside and out that anything that he adds is additive. The other great thing about Hugh is even though he's doing the dialogue word for word, every take is slightly different. He's very much in the moment, so it always feels alive and unique. Each performance is a snowflake.

Did you all have trouble keeping a straight face on set during some of Mr. Reed's particularly eccentric moments? I'm thinking about that Jar Jar Binks impression…

Scott: The tricky thing is we shot these scenes with extended long takes, so upwards of 10 pages of dialogue, recording for 10 to 15 minutes straight.

I do remember the Jar Jar moment. We were so excited to hear how he was going to perform that because he wanted to save it for when we were finally rolling. And we were probably, I don't know, eight minutes into the take, and as soon as he said, "Squeeze me!"… It was really difficult not to totally ruin the take by audibly laughing.

This interview has been condensed and edited for length and clarity.

"Heretic" is now in theaters.