WARNING: The following article contains major spoilers for Stephen King's Pet Sematary, in theaters now.

Stephen King's Pet Sematary was released in 1983, a horror novel that proved to be one of the author's darkest and most depressing books. The story centered around a family that deals with tragedy by trying to resurrect a dead child  through a cursed burial ground. Naturally, it doesn't go well.

The story was first adapted into a film in 1989, becoming one of the most effective horror stories by the writer to be brought to the big screen. But though that film had its share of scares, it doesn't compare to the new version, directed by Kevin Kölsch and Dennis Widmyer. By tweaking certain elements of the source material and refocusing the horror onto more fleshed out characters with fearsome traumas, Kölsch and Widmyer find new ways to terrify the audience with an effective, low-key horror story.

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While most of the narrative focuses on Doctor Louis Creed, both films pay slight attention to his wife, Rachel, and her history with death. In both adaptations, she recounts the fate of her long-dead sister Zelda, who was constantly in anguish after developing spinal meningitis. Left in extreme pain and trapped in her bed, she required the young Rachel to come to her room and feed her regularly. In both films, Rachel is eventually left alone with Zelda, and is present at the time of her death. But while the 1989 film depicts her death as a slow and spiteful thing, it only really comes across in a single scene when Rachel recounts the tale to her husband.

That's not the case in the new film, which sets Zelda as the source of Rachel's trauma and fear of death. The new film gives Rachel a visceral version of her fears, revealing that she was in part responsible for Zelda's death. Afraid to see her sister, she put Zelda's meal into a faulty dumbwaiter and tried to send it up to her for dinner. From upstairs, Rachel could hear her sister drag herself to the meal, and then fall through the opening to her death. The noise still haunts Rachel, and does so consistently through the film, resulting in some very effective jump scares and misdirections. It makes her trauma a part of her story instead of just an element of it, and therefor a more visceral and terrifying aspect of the narrative.

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Ellie The Great And Terrible

One of the biggest changes the creators of the new film make to the original story switching which of the Creed children are killed. In the original novel and first adaptation of the story, it was the young Gage who died when a big rig truck lost control and struck him in the road. But in the new film, it's the slightly older Ellie who ends up killed by the accident. This simple change means that the older and more complicated child is the one who has to be resurrected, and the result is more effective and evil.

Having Gage as the victim means having a small child, who lacks much in terms of physical intimidation or clever tactics, bring the scares. The original film included laughable moments where Gage literally launched himself like some sort of flying bat. Ellie is older and more clever, and brought to life by a more skilled actress, allowing the filmmakers more room to indulge in ruthless tactics for scares.

She employs more strategy than Gage did in the original when she attacks Jud, and uses more weapons to attack her former family. The thing inside her body also gains a clear voice, meaning it has the ability to threaten and mentally break down it's targets before it kills them. Instead of just being a monstrous little child, Ellie is able to be cruel and calculating, stabbing people, and letting them bleed out for greater effect. All this helps lead to the genuinely shocking ending, which is considerably more frightening than the original.

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The Ending Changes Everything

Ellie being a massive threat ends up playing out throughout the climax of the film. After fatally stabbing Rachel, Ellie knocks out her father and drags her mother to the Pet Sematary. When Louis comes too, he chases after Ellie and returns to the haunted woods that house the soiled earth. He fights Ellie, and almost manages to kill her before he's suddenly struck down from behind by the reanimated Rachel. Ellie and Rachel drag the fading Louis back to the Pet Sematary, and the film ends with the three burning down Jud's home and coming to claim to Gage, implying that they intend to kill him and resurrect him too.

It's a sudden and upsetting ending, and one that works perfectly with the overall arc of exploring how grief can destroy a family. While the previous versions of the story ended on ambiguous but despondent note, this gives the story an outright downer ending. The sudden death of Louis is one of the most surprising moments in the film, eliciting gasps from the audience when it hits. But the foreboding and fearsome status of the family at the end of the film, approaching the unsuspecting Gage as a family of monsters coming to collect him, gives the film a more concrete and terrifying conclusion.

Directed by Kevin Kölsch and Dennis Widmyer, Pet Sematary stars Jason Clarke, Amy Seimetz, Jeté Laurence, Hugo and Lucas Lavoie, and John Lithgow. The adaptation of the Stephen King novel opens Friday nationwide.