How 'Knock at the Cabin's ending changed from the book, 'The Cabin at the End of the World'

Over the weekend, Knock at the Cabin became another hit for writer/director M. Night Shyamalan, dethroning Avatar: The Way of Water at the top of the box office and, of course, igniting another round of discussion among Shyamalan fans about the film and its ending. 

As with Old, Knock at the Cabin marks a rare adaptation for Shyamalan, who often sticks to stories based on original ideas, which means there's even more to talk about in terms of how the film wraps things up. Based on Paul Tremblay's novel The Cabin at the End of the World, the framework of the two stories remains largely the same, but the third acts are markedly, sometimes drastically different. So, what changed and why? Let's take a closer look. Here's how the two endings to the same story diverge, and what each has to offer an audience.

**SPOILER WARNING! Spoilers below for both Knock at the Cabin and The Cabin at the End of the World!**

As we've already mentioned, both stories begin almost exactly the same way. Four strangers — Leonard (Dave Bautista), Redmond (Rupert Grint), Adriane (Abby Quinn), and Sabrina (Nikki Amuka-Bird) — show up at a remote cabin where a family of three is staying. Once there, they invade the house and capture parents Eric (Jonathan Groff) and Andrew (Ben Aldridge) and their young daughter Wen (Kristen Cui), then present them with a horrifying choice: Two of them must sacrifice a chosen third, or the apocalypse will descend upon humanity. 

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So far, it's exactly as Tremblay's novel lays things out, and just like in Tremblay's novel, the strangers sacrifice one of their own — killing Redmond with their improvised weapons — when the family refuses to choose a sacrifice. The strangers then turn on the TV and reveal that earthquakes and tsunamis have broken out in the Pacific Ocean, but Eric and Andrew believe it to be a coincidence, and not the beginning of a prophesied apocalypse. 

Things start to diverge with what happens next. In the film, the strangers ask the family to make a choice again, and when they refuse, the strangers sacrifice Adriane, then reveal a massive plague outbreak through TV news. In the book, Abby is about to be sacrificed when Andrew makes a break for it, storms outside and gets the gun he keeps locked in the family car. In the ensuing chaos, Andrew shoots Adriane, then tries to rescue his family. In the film, with Adriane already dead, he shoots Sabrina, who's then finished off by Leonard. 

Now, here's where things get really different. In both the book and the film, Andrew goes back to the house to try and save his family with the help of the gun, and gets into a scuffle over the weapon with Leonard. In the film, Leonard overpowers Andrew through a little trickery and manages to get the gun back, but in the book, the scuffle sets the gun off, and kills Wen. Devastated by the loss of their daughter, Andrew and Eric are told that even though a member of their family is dead, it doesn't count, because Wen died accidentally and not through a willing sacrifice. 

In the book, this sets up an ending in which Sabrina, devastated by Wen's death, loses faith in her mission to prevent the apocalypse. She kills Leonard, leads Andrew and Eric to a car, then kills herself, telling the couple that they still have a few minutes to avert the apocalypse. As the book ends, Eric and Andrew agree that even if they did believe they could save the world through a sacrifice, they don't want to, because they don't want to believe in a God that would allow their innocent daughter to die like Wen died. So, they head off into the world together, carrying Wen's body, come what may. 

In the film, with the other three members of his group dead, Leonard gives the gun back to Andrew and asks the couple to follow him out to the cabin's deck. Andrew and Eric send Wen to her treehouse to shield her from what's about to happen, and Leonard slits his own throat after warning the couple that they only have a few minutes left to make a choice. Back in the house, after Leonard's death, Eric is overcome with emotion, and convinces Andrew to shoot him and prevent the apocalypse for the sake of their daughter. With Eric dead, Andrew and Wen find Redmond's truck, leave the woods, and visit a diner, where they see news report that the apocalyptic events of the last two days are receding. For Knock at the Cabin co-screenwriters Steve Desmond and Michael Sherman, it represented a more optimistic (if still dark) way to end the story. 

"The book is the book, and the movie is the movie, and we think they both were exceptional medium," the writers told Variety after Knock at the Cabin's premiere. "This is a big, wide release movie that is meant for a very large audience. There are some decisions that the book made that were pretty dark and may have been a little too much for a broader audience. That was a decision that [Shyamalan] immediately recognized. It’s a great ending now.” 

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On a lot of levels, this "great ending" can be read as something quite optimistic, as it proves that a small act of sacrifice can indeed have big consequences, and that selflessness is a viable path to saving other people. Throw in Eric's meditations on how the strangers represent all the different facets of humanity, and may indeed be the Four Horsemen of the Apocalypse, and you've got a story that examines the high stakes of the end of the world on a very intimate scale, something Shyamalan loves to do. 

But while the ending of the book does result in the senseless death of a child, Tremblay doesn't necessarily feel that he wrote the darker version of the story. Here's how explained his take on the book's ending to Variety:

“I find it horrific there’s this higher power that is just going to willy-nilly sacrifice humans for everybody else,” he said. “It doesn’t seem like a very moral thing to do, so I don’t find it that hopeful. I find the idea of what happened in my book — that the two characters reject that, like ‘No, we’re not going to sacrifice. That’s wrong. We’re going to go on.’ That’s a little bit more hopeful.”

Tremblay's book was written and released at a time when the madness of the wider world seemed to be building, and the tone of the book digs heavily into that feeling that the whole world is shouting at you and your family that it's the end, and that you must make tough choices even when they're not fair, because some greater power demands it. In a world in which people of many faiths were making demands of many kinds, Tremblay wrote a story in which two people refused all of those demands, and chose to depart with their own inherent goodness and love intact. It's sad, and it's dark, and it's ambiguous, but it is in its own way quite optimistic from an emotional point of view, and for a lot of people it will remain the superior ending. 

Still, Shyamalan did what he always does, and took big swings with a high-concept story that will keep people talking for a very long time. Changes and all, Knock at the Cabin works in its own way, and is made even more fascinating by how it chose to adapt the novel. 

Looking for more horror to make your spine tingle and blood curdle? You can currently catch Jordan Peele's NOPE on Peacock. Plus, don't miss SYFY's hit horror series Chucky, which was just picked up for a third season.