Cobweb Ending Explained: Beware What Crawls Inside The Walls
This article contains major spoilers for "Cobweb."
As anyone with arachnophobia can attest, there are few moments more horrible than looking up at the ceiling for the giant spider that was there only a moment ago, only to find nothing there. Well, except maybe the moment where the giant spider reappears on your pillow, a few inches away from your face. Samuel Bodin's 2023 horror film "Cobweb" preys on that kind of fear with a monster who is unseen for most of the movie's runtime, and who hides under on ceilings, under furniture, and inside the walls in the film's blood-soaked final act.
The fact that there even is a monster is hidden for much of the movie, which instead presents young Peter's (Woody Norman) parents, Carol (Lizzy Caplan) and Mark (Antony Starr), as human monsters who just might kill him and bury him in the pumpkin patch if he doesn't behave himself. It's smart casting: Caplan came to the film after starring as Annie Wilkes (the homicidal "number one fan" from Stephen King's "Misery") in "Castle Rock" season 2, and Starr is best known for playing the even-more-homicidal villain Homelander in "The Boys." For audience members who have seen them in those roles, both Caplan and Starr are plausible as horror antagonists. Carol has a jittery, desperate, neurotic energy tinged with her own unspoken fears, and Mark exudes a quiet menace that hints at barely-restrained violence.
Add a story about a missing girl in the neighborhood and a skeleton buried in the pumpkin patch, not to mention Carol and Mark imprisoning Peter in a hidden basement with its own hidden dungeon, and it's little wonder that he's frightened of them. A voice in the walls (Olivia Sussman) tells him she's his sister, trapped by their evil parents, who have dark plans for Peter as well. But all is not as it seems...
What you need to remember about the plot of Cobweb
Eight-year-old Peter is withdrawn at school, has no friends, and is targeted by bullies, but the real cause of concern for his new substitute teacher, Miss Devine (Cleopatra Coleman), is a drawing Peter does of a child surrounded by darkness, with the words "HELP ME." After visiting the family home and being turned away, she tells the school principal (Jay Rincon) that something is "off" about Peter's mother. But without more substantial grounds to investigate, she's warned to stop being nosy about his home life.
Likewise, the audience doesn't initially see Peter's parents doing anything outright monstrous, but there's definitely something off about them. The first scene of outright abuse is when Peter is locked in the basement by his father — a decision not triggered by Peter pushing a kid at school down some stairs and breaking his arm, but by Mark subsequently learning about the picture Peter drew. When Miss Devine visits the home for a second time and comes close to hearing Peter in the basement, there's a constant threat of imminent violence as Mark menacingly holds a hammer. But Miss Devine ultimately drives away unharmed. Mark tells Peter, "We are not a family that solves our problems with violence."
This seems at odds with the body that Peter finds in the pumpkin patch after being told where to dig by the voice inside his bedroom wall. She tells him that it's the body of a trick-or-treater who mysteriously went missing years ago, and that Mark and Carol killed her because she caught sight of Peter's poor, imprisoned sister. Peter's sister tells him that he will meet the same fate as her ... unless he does something to stop it.
The pumpkin patch lesson
While the whispers from Peter's sister in the wall persuade him to push Brian (Luke Busey) down the stairs at school, she might not have been able to tip him over into outright murder by herself. But Mark sows the seeds of his own destruction when he takes Peter out into the pumpkin patch to dig a hole and bury pumpkins that have been corrupted by black rot. "Blight like this, it spreads fast. Get rid of it now, or all the healthy pumpkins will get infected. And we can't have that," Mark tells his son ominously. "We're going to bury the pumpkins, and we're going to hope that the next crop is better. Better luck next time. You understand?"
It's effectively a confession of what Peter has been told by his sister: that their parents trapped her inside the wall to isolate her from their second child, hoping that the next "crop" would be better. It's not completely clear what Mark wanted Peter to "understand" — perhaps it was simply that he should put his bad behavior in the past and start over fresh, or perhaps it was a threat to imprison or kill him. Peter certainly interprets it the second way, and decides that the best defense is a good offense.
What happens at the end of Cobweb?
Fearing that his parents will kill or imprison him, Peter makes his move on Halloween. When the family sits down to their meal of brown gruel, Mark and Carol eat it, but Peter only plays with his food. Too late, Mark realizes that the food tastes better than it usually does due to an added flavor of cinnamon, which also happens to be the flavor of the rat poison that Mark put down earlier. The poison soon kills Mark, and Peter finishes Carol off by kicking her down the stairs and causing her to accidentally stab herself with her own knife. Curiously, though, her last words to Peter are a warning: "Don't let her out."
Peter, unfortunately, doesn't listen. He pushes the heavy grandfather clock away from a hidden door in his parents' bedroom, and uses Carol's keys to unlock the door. As soon as his sister (who is named in the credits as Sarah, though her name is never spoken out loud in the film) realizes she's free, her voice changes from that of a little girl (Olivia Sussman) to something older, deeper, and more monstrous (Debra Wilson). She drops the act of being an innocent victim, and reveals that it was she who killed the trick-or-treater; Mark and Carol only buried the body to cover up the crime.
As Sarah explains to Peter (while holding the severed head of one of the bullies who picked a bad time to try and get back at Peter by trashing his house), she really is his sister, and she really was locked away inside the walls by their parents. The question of when Sarah became monstrous, however, is a little more complicated.
Nature vs. lack of nurture
The build-up to the full reveal of Sarah (played in the flesh by Aleksandra Dragova) certainly makes it seem like she's truly monstrous. She scuttles around in the corners of vision and picks off her victims with inhuman strength and speed; her voice sounds like something out of a nightmare. But when Sarah's face is finally shown, it's really the only basic aspect of her physicality that's "deformed." Though she moves like a spider, she only has the usual four limbs. And other frightening aspects of her appearance, like her long, tangled hair and her talons, are the result of being trapped inside a wall for her entire life without access to a comb or nail clippers.
When Sarah tells Peter the story of her own childhood, it's clear that the imprisonment preceded anything that might have been done to deserve it. "When I was born, they screamed," she reveals. "So Daddy made me a pit. Then he made me a cage." Despite her gravelly voice, Sarah indicates that she's not actually much older than Peter when she adds, bitterly: "While you were whining in this warm bed, I was suffering among cobwebs and rats, learning how to climb."
Perhaps Mark and Carol are the real villains of the story after all. Building a dungeon is not exactly a rational response to having a baby with a facial difference. And many aspects of Sarah's monstrosity — her gravity-defying crawling, her lethal strength, and her homicidal urges — may simply be the product of a monstrous upbringing.
Why didn't Sarah just break through the walls?
Speaking of Sarah's superhuman strength, one question that has cropped up a lot in discussions of the film is why Sarah needed Peter's help to break out of her prison. We see Miss Devine breaking through the wall with a fireplace poker in a reality short amount of time, yet Sarah couldn't manage to make more than a small hole despite being able to rip heads off with her bare hands.
It helps to recognize that "Cobweb" is deliberately designed in the style of a fairy tale — the Grimm kind. It's the type of fairy tale where parents abandon their children in the woods to die, lock them in a tower without access to a hairdresser, or — in the case of the stepmother in "The Juniper Tree" — decapitate them, dismember their body, put it in a stew, and trick the family into eating the cannibal stew. (Disney probably won't be making an animated musical out of that one any time soon.)
Director Samuel Bodin has discussed the fairy tale aspects of "Cobweb" in many interviews, particularly when it comes to Sarah's appearance. "I wanted her to have something of a fairy tale, very very long hair," he told The Digital Fix. "It was a kind of naive projection of a monster, of a bad sister, the worst sister you can imagine." Following that thread, Sarah doesn't break out of the walls by herself for the same reason that Rapunzel doesn't simply cut off her hair and free herself from her tower. It's best not to overthink it.
'When you put something in your mind it can eat you all your life'
At the very end of "Cobweb," Peter and Miss Devine succeed in trapping Sarah in the basement dungeon and escape the house — but not before Sarah taunts Peter one last time. After robbing Peter of sleep for much of the film, his sister tells him that his fear of her return will now plague him every night for the rest of his life: "Every creak, every groan, every tap in the wall, you'll think of me." The speech is intercut with scenes that could be a flash-forward, or could simply be a visual representation of Sarah's warning. In them, Peter is seemingly safe in a new home, but soon finds that his sister has caught up with him again.
Again, it's not an ending that's particularly friendly to real-world logic. Some viewers may be left frustrated by not knowing what happens to Sarah — whether Miss Devine calls the police to report the feral child in the dungeon, or whether she's simply left down there to rot (or escape). But Sarah's point is that it really doesn't matter what happens to her physical body; she's already wormed her way into Peter's head.
"When you put something in your mind it can eat you all your life. And that's the idea, is that from now on you won't be okay whatever you do," Bodin explained in an interview with Radio Times. And Peter will be haunted not only by his sister, but by his choice to murder his mother and father. "She says to him, 'You are a killer, too.' And that's a fact, you know?" Bodin pointed out. "So the question is, oh, maybe they have something in common."