Primate (2025) Ending Explained – Nature Bites Back
Movie Details: Director: Johannes Roberts | Runtime: 1h 29m | Release Date: Sep 18th 2025 | Star Rating: 3.5/5 Stars
Welcome to Knockout Horror. Today we are going to be explaining the ending to the horror movie Primate (2025). I thought this movie was a ton of fun; our review will follow shortly. Naturally, the ending isn’t hugely complex but let’s break down some of the events and offer up a few interesting rabid monkey based facts, too. Let’s go!
⚠️ Warning: Major spoilers follow below.
The Ending in Brief
The TL;DR: After Ben the chimp decimates almost the entire damn friend group, leaving a trail of bodies across the estate, Adam (Lucy’s deaf father) arrives home. A final showdown ensues in the living room where Adam, Lucy, and Erin fight for their lives. Adam manages to stab Ben with a shattered wine bottle, but the chimp keeps coming. In a final act of aggression, Ben tackles Lucy over the balcony railing. Adam catches Lucy, but Ben falls to the patio below, where he is fatally impaled on the leg of a broken chair. As the police arrive to secure the scene, an officer collecting evidence accidentally triggers Ben’s tablet soundboard, which plays the phrase “Lucy Bad”. This leaves Lucy devastated and just a little harrowed, suggesting the impact of this day will linger long after Ben is already gone.
Who Survived? Only the family unit survived: Lucy, her sister Erin, and their father Adam. Every single friend and guest was killed. This movie had a fantastic kill count!
Why Did Ben Go Crazy? Ben was bitten by a mongoose that had invaded his enclosure. The mongoose was carrying rabies, which transmitted to Ben. The aggression was a result of the disease taking hold, compounded by his already territorial nature as a chimp.
What Did The Final Message Mean? It’s more of a suggestion than anything. The phrase “Lucy Bad” implies that, despite the rabies, Ben retained some cognitive function and awareness. He likely blamed Lucy for leaving him for college, interpreting her absence as abandonment. Remember, it’s the same message Erin played for her when Lucy first returned. It’s one last emotional knife-twist suggesting that her absence lead to chaos.
Good to Know: Chimpanzees are hydrophobic. Their low body fat and dense muscle mass make them sink like stones. This is why the group was safe in the infinity pool for so long; Ben physically could not enter the water without risking drowning, forcing him to stalk the perimeter instead. This is the exact reason you see moats around chimp enclosures in zoos.
Table of Contents
Primate (2025) Ending Explained
As always, I am not going to bore you with a scene-by-scene recap of the plot. You just watched the movie, you know that the monkey went bananas (sorry, I had to) and killed everyone. Let’s dig into the themes, the logic, and that incredibly bleak ending. Quick sidenote: Was anyone else shocked by this film’s kill-count? I was expecting a lot of plot armour for the teens. Good stuff!
Why Was Ben So Aggressive?
The primary reason for Ben’s rampage was the rabies virus, transmitted via a bite from an infected mongoose. However, the film implies there was more bubbling under the surface than just a viral infection. Ben was already displaying signs of stress and abandonment issues before the symptoms fully set in.
It’s quite important to remember here, that this was an animal that had been used in linguistics research. It didn’t have a cushy life. It was likely ripped straight from its mother’s arms, something that often results in the mother being tragically murdered. It then lived its life in the confines of a research facility.

Chimpanzees are incredibly social creatures. In the wild, they live in large communities with complex hierarchies. Ben was living in isolation, with his only “mother” figure (Lucy’s late mum) for company. His social group was expanded when he was brought home but the damage was already done. These are creatures with enormous brains and they don’t forget easily.
Compounding that was the fact that his “mother”, Lucy’s mum, died and his “sister” (Lucy) abandoned him for college. This was a suffering creature who was dealing with tragedy and isolation. The rabies removed his inhibitions, but the rage was likely fueled by years of confusion and abuse. He didn’t just attack them blindly; he hunted them with a level of vindictiveness that suggests he knew exactly who they were.
Did You Know: The Travis Connection: Ripping From The Headlines
While Primate plays out like a slasher movie, the horror is rooted in a very real, very tragic event. The film draws heavy inspiration from the story of Travis the Chimp, a ‘domesticated’ animal who, in 2009, mauled his owner’s friend in Stamford, Connecticut.
Much like Ben in the movie, Travis was treated like a human, drinking wine, using a computer, dressing in clothes, and being doped with Xanax to keep him calm. The film’s specific brutality, particularly the scene where Doug Lambert has his face torn off, mirrors the injuries sustained by Travis’s victim, Charla Nash.
Luckily Charla survived but not without severe injuries. She lost her eyes, lips, and nose. It serves as a grim reminder that these are apex predators, not furry children, and treating them as such usually ends in bloodshed.
The Pool Strategy: Why Did It Work?
Jumping into the pool worked because chimps are hydrophobic. One of the smarter parts of the movie was the group retreating to the infinity pool. As mentioned in the “Good to Know” section above, chimps are notoriously bad swimmers because they are just too damn hench. Their muscle density is too high, making buoyancy almost impossible. Ben, knew this and so did Nick who suggests jumping in the pool.

It created a stalemate. Ben was the superior predator on land, much faster and stronger than any human, but the water was an impenetrable barrier for him. The tension came from the fact that humans can’t tread water forever. It turned the luxury feature of the house into a bit of a siege tower, although Nick’s death proved that even the high ground isn’t safe if you get too close to the edge.
This is why the friends were willing to risk their lives to grab the pool float. It was the only way they could stay up in the water permanently.
Unpicking The Logic: The Rabies Timeline
Here is where the movie stretches credibility to breaking point… Well, the most egregious time it stretches logic, anyways. Ben gets bitten by the mongoose and goes full 28 Days Later within about 36 hours. In reality, the incubation period for rabies in primates is usually much longer, often weeks or months before symptoms appear.
While there are “furious” strains of rabies that act faster, the speed at which Ben deteriorated from a cuddly pet to a tactical killing machine is pure Hollywood fiction. The virus travels along nerve pathways to the brain; it’s not an instant zombification switch. But hey, watching a chimp wait three months to get slightly irritable wouldn’t make for a very exciting Saturday night watch, would it?
Why Their Deaths Mattered: The Uninvited Guests
Can we talk about how absolutely insufferable the friends were? Kate bringing Hannah without asking is bad enough, but Hannah inviting two random guys (Drew and Brad) she met at the airport to a secluded family home is the kind of behaviour that usually gets you brutally bifurcated in a horror movie. And, well, it did but not in the way you would usually imagine.

Their deaths did serve a specific narrative purpose, though: they were intruders in Ben’s territory. To a confused and rabid ape, these loud, unfamiliar males entering his “nest” were an immediate threat. A threat that he was more than equipped to deal with. That jaw rip death is one of the most brutal I’ve seen in awhile.
It also highlighted the stark difference between the “influencer” lifestyle of the friends, who were obsessed with the pool and the ‘vibes’, and the primal reality of nature that they had stepped into. They were way out of their depth.
Reality Check: Do Chimps Actually Rip Jaws Off?
Ben’s signature move, tearing the lower jaw off his victims, might look like a Mortal Kombat fatality, but it is based on terrifyingly real animal behaviour. While physically detaching the mandible bone is a bit of a Hollywood stretch, chimpanzees are infamous for inflicting “de-gloving” injuries.
When attacking rivals or humans, chimps instinctively target three specific areas: the face, the fingers, and the genitals. They don’t strike; they bite and pull with immense strength. The goal is tactical mutilation… Destroying the hands stops the victim from grabbing weapons, and destroying the mouth stops the victim from biting back.
In the tragic real-life case of Travis the Chimp, the victim suffered catastrophic facial injuries that mirrored the aftermath of Ben’s attacks in the movie. So, while the “clean rip” is special effects wizardry, and a ton of horror-fun, the intent is scientifically accurate.
What Did “Lucy Bad” Mean?
Lucy Bad was symbolic of both Lucy and the family’s treatment of Ben, and how their actions lead to this outcome. This is the gut-punch of the entire movie. As the police are bagging evidence, the soundboard speaks: “Lucy Bad”.
Throughout the film, Lucy convinced herself that Ben was “sick” and that the creature attacking them wasn’t really *him*. She clung to the idea that the virus was driving the bus. However, that final recording implies that Ben was conscious of his actions to the very end. He very deliberately left that message for her to find; with the assist from the police, naturally.

It suggests that Ben blamed Lucy for everything. He blamed her for leaving him alone in that cage while she went off to college. He blamed her for bringing strangers into their home. The tragedy isn’t just that the family pet died; it’s that he died hating the person he loved the most.
It completely deconstructs the “Disneyfication” of wild animals… Ben wasn’t a fuzzy little human who understood forgiveness; he was an intelligent creature capable of holding a grudge and acting on it in the most entertainingly gruesome way of all.
The Body Count: Who Died and How?
Primate didn’t exactly hold back on the gore. Here is the final tally of Ben’s rampage:
- Doug (The Vet): Face torn off inside the enclosure.
- Nick: Thrown off the infinity pool edge; death by gravity.
- Kate: Head crushed with a rock while retrieving a phone.
- Drew: Jaw ripped off in the bedroom.
- Brad: Beaten to death with a shovel.
- Hannah: Mauled inside the car after Ben unlocked it.
- Ben (The Chimp): Impaled on a chair leg after a balcony fall.
Total Human Casualties: 6
Survivors: 3 (Adam, Lucy, Erin)
Social Commentary: The “Chimp Crazy” Effect
Primate fits neatly into the current wave of media re-examining our relationship with exotic pets. Following the success of HBO’s Chimp Crazy, audiences are becoming more aware of the darkness behind the cute Instagram videos.

Adam, the father, represents the arrogance of ownership. He believed his money and the fancy enclosure could override millions of years of evolution. He thought he could domesticate the wild. The film punishes this hubris severely. The “elaborately designed house embedded into a cliff” becomes a prison, and the “custom soundboard” becomes a tool for the killer to taunt his victims.
It’s a harsh critique of the idea that we can own nature.
Frequently Asked Questions
Will Lucy and Erin contract rabies?
No, Lucy and Erin, despite being bitten and scratched by Ben, should have time to receive a series of rabies jabs which will inoculate them from the virus progressing any further.
Did the mongoose really have rabies?
Yes. Adam received a message from the lab confirming the mongoose tested positive for rabies. He ignored the text because he was distracted by his work and the stress of the situation, a fatal error that cost almost everyone their lives.
How did Hannah die?
Hannah’s death was a comedy of errors. After sneaking out to a car, she realised she had the wrong keyfob. She locked herself in the wrong car and called 911. Unfortunately, Ben was given the correct key-fob by Drew earlier in the film as he attempted to distract him. Ben, showing his high intelligence, unlocked the car remotely, allowing him to open the door and maul her.
How did the the police find the house?
Hannah managed to call the police before she was killed by Ben and the police traced the call.
Why couldn’t Adam hear the attacks?
Adam is deaf. This plot point was crucial because it isolated him from the chaos. While his daughter and her friends were being slaughtered in the backyard and pool area, Adam was likely working or sleeping, completely unaware of the auditory carnage happening metres away.
Is Ben based on a real chimp?
Ben appears to be an amalgamation of several famous chimps, notably Travis (the attack profile) and Washoe or Nim Chimpsky (the sign language and soundboard usage). The film combines the intellectual potential of these animals with their physical danger.
What happened to the Vet, Doug?
Doug Lambert was the first victim. He entered the enclosure to check on Ben and was immediately attacked. The film doesn’t shy away from the gore here—Ben tears his face off, establishing the stakes immediately.
Final Thoughts: Nature Bites Back
Primate (2025) isn’t exactly high art but man did I have a good time with it. It’s a schlocky, violent creature feature that relies a bit too heavily on characters making stupid decisions. But as an exploration of the terror of a domestic pet turning on its owners, it is really effective. The ending, with its cruel emotional twist, elevates it slightly above your standard SyFy channel trash. Just remember: if you love wild animals, leave them in the wild. Thanks for reading!
Thank you very much for reading. Why not stick around? Check out some more Ending Explained articles. I also review horror movies and I also write horror lists.
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