Cellar Door (2024) Ending Explained - What, Exactly, Is Down There?

Welcome to Knockout Horror. We reviewed brand new movie Cellar Door just a few days ago. We found it to be a fairly middling thriller that never really lived up to the potential of its intriguing premise. Something which is kinda sad because the concept was pretty great. After all, I can bet that the majority of people who watched this movie did so because they wanted to know just what was behind the cellar door.

With that being said, you are, probably, here because you are wondering just what the hell happened. Well, I am here to explain the ending to Cellar Door. Obviously this article will contain spoilers so consider yourself warned. I do apologise for getting kinda wordy, here. This is a long read but it is real tough to condense these articles while avoiding missing details.

Quick Summary

Let’s summarise Cellar Door then get to the answers. Couple John and Sera have been trying for a baby but have had little luck conceiving naturally. Probably not a surprise given that actor Scott Speedman is 49 and Jordana Brewster is 44. That biological clock doesn’t hang around for anyone. They have gone through IVF treatment and Sera is finally with child. The two set about preparing the house, probably a bit premature given that Sera isn’t even showing, yet. Unfortunately, Sera suffers a miscarriage. She attempts to call John for help but he doesn’t respond, seemingly, otherwise engaged. Something we will get back to later on.

After the traumatic experience, the pair decide they need to leave their house. There are too many bad memories tied to the place. They set about looking for property in a quaint little town. The only problem is that the community is very insular and unwilling to sell to outsiders. Also, apparently, a mathematician and an Architect don’t make enough money to afford anywhere nice. Median salary of an architect, in the USA, is anywhere between $90,000 per annum and $120,000 per annum and a mathematician has the average of $112,000 so I am not sure what their problem is. I guess property is even harder to come by in the US than the UK.

An Insane Gift

Their estate agent refers them to a well connected local man called Emmett under the assumption that he can help them out through the people he knows. After meeting Emmett in his wonderful mansion, they spend the night. Awaking the next morning to find that Emmett has left and actually gifted them the property with just one caveat.. They must never open the cellar door. If they open it, the house goes back to his ownership. Pretty cool? Definitely! Highly unlikely? Oh God yes. This is a farcical plot but here we go.

Sera wants to accept, John is sceptical because who the hell gives away a house? Sera convinces him to put aside the concerns and accept the property. At a house warming party, friends enquire about the cellar door and try to convince John to open it. After all, how will Emmett know? We also learn, at this party, that John has been having an affair with a co-worker called Alyssa. He has called things off to focus on his upcoming child. Alyssa has brought along a gift for them, a Jasmine plant. This will come into play later on.

A man turns up at the house looking dishevelled and carrying gasoline. He tells John that he needs to burn it all down. We will explain this point in a bit. Naturally, the excitement of the new home makes Sera horny, her and John bump uglies which will lead to an impending pregnancy.

Things Go Wrong

John arrives into work only to be told he has to leave. Alyssa has filed a sexual harassment claim against him. We will get into this in a little. Upon arriving home, John realises he can’t tell Sera what has really happened as it will mean he has to admit the affair to her. Instead, he stays at home while Sera is at works and spends his time running while she is home. Keeping up the pretence of still being employed.

During his time off work, John decides to investigate the blueprints of the house to find out just what exactly the cellar is hiding. He finds, through the blueprints, that there is a secret door that hides a crawlspace. The crawlspace leads to a barred up door into the cellar. John drills a hole into the wall so that he can see into the cellar. Before he finishes, Sera arrives back home, prompting him to stop.

John is contacted by Alyssa and requests to discuss things. The pair meet up in a parking garage and it is revealed that John had promised her that he would leave Sera. He had told her that they would live in a perfect house together and start a family. Alyssa feels as though Sera has stolen all of that from her. John, once again, reaffirms that the affair is over and that he loves his wife.

Things Go Badly Wrong

The next day, Sera realises that she is pregnant again. Her perfect life is coming together, finally. The only problem is that Sera finds the home’s blueprints that John was hiding and realises that John has been trying to find a way to get into the cellar. This would ruin everything for Sera, obviously, and mean they would have to give the house back to Emmett, as per the agreement. Oh, and to make matters worse, Alyssa has just turned up at the house to tell Sera exactly what John has been up to.

Things are about to go badly wrong. Alyssa can’t find Sera so roams the house, eventually stumbling on the pregnancy test and realising that Sera is pregnant again, all while Sera is examining the crawl space behind the secret door. John, moments later, sees Alyssa’s car speed away from his home while he is chatting on the phone to his boss. He pursues Alyssa but can’t keep up.

John comes back later that night. Sera informs him about her pregnancy and, also, that she knows about him snooping into the cellar. She ask him to promise that they are in this together and that he won’t do it again, he agrees. She makes him close up the crawl space by nailing it shut. This will be important later. John is invited back to work, Alyssa has gone on a break and the investigation has deemed him to be innocent of the harassment.

We later learn, however, that Alyssa has gone missing and the police are investigating. John was one of the last to see her, after all. In the meantime, Sera has learned about John not being at work, thanks to a chance conversation with the estate agent from earlier who has been meeting John on his daily runs. You know, the ones that took place when he claimed he was in work? It is obvious now, to Sera, that John has been lying to her.

Explaining The Ending

So this is, probably, the part which needs explanation. In short, Alyssa is missing and her car has been found abandoned. The police are investigating and John is a suspect. When Sera is deciding on a colour to paint the nursey, John finds a random bullet in the wall. He soon realises that said bullet came from a box of ammo in the house and was, likely, fired from one of the guns on the display cabinet. Sera tells him to drop it and that it was probably a coincidence.

Police turn up to question John about Alyssa’s disappearance as phone records suggest he was the last one to speak to her. Her phone, also, pinged near their home the day after he spoke to her. John denies any knowledge of what happened but the police asking him if anyone can corroborate his whereabouts stumps him. Sera interjects with an alibi for him. Claiming he was with her her the whole time so couldn’t have been involved.

Sera Knew Everything

In reality, Sera knows exactly what has been going on. She has examined both John’s phone and his emails and seen his history with Alyssa. She knows Alyssa was telling the truth about the pair having a sexual relationship but that it was consensual. In fact, it has been going on for a long time and the reason Sera couldn’t get in contact with John, while she was suffering a miscarriage, was because he was in a house getting intimate with Alyssa. Meaning he ignored her calls and left her to suffer alone.

Alyssa loved Jasmine plants, remember the one she gifted to the couple at the housewarming party that Sera discarded at the side of the house? John had come home from a liaison with Alyssa smelling like sex and Jasmine so Sera put two and two together after the party. He only broke things off with Alyssa after the miscarriage, likely down to guilt. Sera knows all of this and only covered for John as she didn’t want to have her baby grow up with a dad in prison for murder.

John visits the house of the previous owner who tells him that the only way to save himself and Sera is to break the contract and open the cellar door. John heads back and confronts Sera about covering up the bullet hole and painting the walls of the nursery. He tells her the house is changing her and he needs to end it all by opening the cellar door. John grabs a crowbar and heads out to the garden. He starts smashing open the lock. Before he can actually open the cellar door, Sera hits him over the head with the crowbar, rendering him unconscious.

So What Happened?

This is the tell all part of the movie. Sera has been up to no good and she has been doing it to preserve their dream life in the house. Fast forwarding a bit to earlier events in the movie. Alyssa came over to the house while John wasn’t home. She was going to tell Sera everything, I assume. Alyssa found the pregnancy test on the bed. Sera heard a noise and assumed there was an intruder in the house. Grabbing the gun, she headed upstairs and confronted Alyssa. Alyssa was beside herself, claiming that Sera stole her perfect life. She advanced towards Sera who shot her multiple times in the stomach. Rather than calling the police as, after all, she was just defending herself. She decides to finish Alyssa off.

Sera strangles her, wraps her in drop sheets from her decorating and drags her downstairs. She places Alyssa’s body in the crawl space. Remember how she made John seal the crawlspace up earlier in the film? She did this to implicate him in the crime. Alyssa’s body was sealed away and John’s fingerprints will be all over the nails, wood, and hammer that did the job. His prints will also be on the bullets and gun as he found them earlier.

Sera steals Alyssa’s car and speeds away from the house. Remember John seeing it drive past while he was on the phone to his boss? It was Sera driving, not Alyssa. Sera managed to lose John, she uploaded some photos using Alyssa’s phone and emailed Alyssa’s boss, acting as if she was Alyssa, asking for time off for “self care”. The whole scene was planned out to look as though Alyssa had committed suicide in a remote location or simply left the country. Sera burned her clothes to hide any evidence but she made one mistake. She missed a shot, leaving the bullet in the wall that John found. Ruining her plan completely.

Why Did Sera Kill Alyssa?

Sera did all of this with one simple goal in mind, preserving the couple’s way of life. She wants a perfect house, a perfect relationship and a perfect life. Alyssa threatened this and so she killed her and used the event to bribe John into staying away from the cellar and staying with her. Alyssa tells John that, if he leaves her, he will die.

Her elaborate plan involves shooting him, there and then, and telling the police she did it in self defence. She will testify that it was John who killed Alyssa. He lured her to the house, murdered her, buried her in the crawlspace and sealed it up. Sera only found out when the police turned up and she found Alyssa’s phone in John’s possessions. Sera tried to confront him about it, he attacked her and she was forced to shoot him in self defence.

John only has one option, agree to go along with Sera’s plan or she will kill him. Even if she doesn’t kill him, she would tell the police that he killed Alyssa and would, likely, have enough evidence to back it up. Even though I am sure when they recovered Alyssa’s body they would recognise that the hand print bruises around her neck were most definitely not made by a man but, whatever. He would go to prison for life.

So John’s hands are, pretty much, tied. He agrees to go along with Sera’s maniacal plan and the two stay together. Alyssa is seen as a tragic runaway or suicide, having killed herself in a place where nobody can find the body. John and Sera stay together but John, obviously, isn’t tremendously happy. Haunted by everything that has taken place. The pair are seen holding a baby shower. Emmett has sent them a gift, the key to the cellar door. Whether they choose to use it or not, is up to them. He is pretty sure they already know what is inside.

So What Was Behind the Cellar Door?

Absolutely nothing, there was nothing behind the cellar door. The cellar wasn’t hiding some big secret or the bodies of Emmet’s family. It was hiding nothing. The cellar door is simply a metaphor for the things we hide to preserve a perfect life. You throw boxes down there, you stash old furniture down there. Basically, anything that you don’t want people to see. Anything that ruins the image of a perfect household, ends up in the cellar.

Sera and John were both hiding things in their own proverbial cellars. John was hiding the sordid affair that he was having which lead to his wife suffering through a miscarriage alone. Rather than confronting the truth and being honest, he hid it away in an attempt to present himself as the perfect husband. Despite the damage this did to Sera and to himself.

Sera was even worse, willing to hide anything in that proverbial cellar including murder. The desire to maintain a perfect life made her a murderer. A fact that she was willing to keep hidden purely to preserve her picture perfect life in the massive house with a loving husband and a young child.

Nothing But a Metaphor

The house was a metaphor for the life people desire to live and the cellar door is a metaphor for the things we hide to keep it that way. The house brings out the worst in people, just like trying to live a perfect life does. It also means you have to hide uncomfortable truths away deep inside you to stay living in that perfect life.

The man who used to live in the house ruined his sobriety due to feeling he was invincible thanks to the picture perfect life he was living in the house. This cost him his family who left him, leaving him destitute and living in a small apartment as a raging alcoholic. His telling John to “open the cellar door to free himself from the contract” was the metaphorical equivalent of telling him to own up to his mistakes and guilt. That’s the only way to release himself because the picture perfect life isn’t real and the proverbial cellar door staying closed will always eat at him and leave him unhappy.

Emmett sending them the key was basically a way of telling them that they know what is in the cellar now. All of their lies, deceit and hidden secrets. Nothing more. The final shot shows Jasmine growing around the cellar door. It’s the same Jasmine that Alyssa gave the pair at their housewarming party. Remember Sera throwing the plant out down the side of the house? It now serves a constant reminder of what they did. Again, acting as a metaphor that the things you hide will still be there waiting for you and you can’t hide them forever.

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