In case you can't watch that video, the lady vampire is attacked by the man's cat collection. Cats fly at her from all directions and drive her away from her intended victim, or more accurately, the actress is pelted with unmoving cat puppets like she's in some PETA-unapproved version of dodgeball, and said kitty-puppets then pretend to bite her in an orgy of unintended puppet-hilarity.

Why It Ruins Everything:

When I first saw this scene and experienced the audience around me guffawing in hearty laughter, I thought it was because the cat-puppet effects were so bad. Because let's face it: It's a Swedish horror movie, they weren't working with a Michael Bay budget here. But now I think that there's more to the awfulness of this scene than just the "bad puppet" aspect. Even if the filmmakers had spent $56 million and produced a photorealistic cats-attacking-vampire masterpiece, the scene still would have been ridiculous, because cats on screen just can't be that horrifying.

Look at this guy's adorable little head!

"Cat yowls off screen after a character throws something" is a comedy staple for a reason, and that reason is not that animals in pain are hilarious. Cats just have a tendency to be inherently funny. I think it's the gulf between their dignity and their real-life helplessness. A small dog falling off a chair is not funny. A cat falling off a chair is funny, because a cat will fall off that chair with an air of quiet, self-assured dignity, and then look at you afterward like it meant to do that.

Whatever the reason behind kitty-hilarity, audiences are primed to find anything cat-related funny. So while the book that Let the Right One In is based on can pull off the cat-attack scene and actually make it rather touching and poignant, you just can't do that with cats on the screen. Add in some terrible puppet effects, and the result is an audience that's still giggling half an hour later at the adorable little critter chewing on a vampire's leg.

That's fine so far, but then comes the ending, which ruins everything. Ending-ruinings are the worst, because you've just spent two hours of your life preparing for a movie to be good, only to see that hope shatter in front of you like a balloon full of cockroaches. It's like watching a gymnast bounce her way through a perfect routine, only to let out a huge, roaring fart in the middle of her last jump. In this particular movie, the ending-fart is this:

The people Eli fought, killed, and eventually died for just so that he could bring them that one copy of the Bible? They print it out, bind it, and stick it on a shelf next to a bunch of other books.

Why It Ruins Everything:

Now, the problem here isn't about one's thoughts on the Bible (or any religious book). Whether you believe that the Bible is the perfect life instruction manual or just a handy heavy thing for squashing centipedes, we're dealing with the book's importance in the context of the movie. And in this movie, viewers have invested two hours of their time and their emotions into Eli's struggle to get his book to a receptive audience. Viewers are then forced to watch the fruit of that struggle dumped in a sad, abandoned-looking library while the "receptive audience" heads back out to play foosball or something. Eli's actions would have had about as much effect if he'd just stayed home and recited the Bible to his pets.

It's kind of like Eli had been carrying the world's last packet of ketchup, fighting off people who wanted to put it on their inferior, soggy french fries. And then he finally reached humanity's last surviving french-fry connoisseurs and dropped the dusty ketchup packet at their feet, only for them to toss it in the back of a fridge somewhere because mayonnaise on fries is way better anyway.

In Dear John, the troubled white couple is John and Savannah. Their years-long quest to decide whether they truly love each other is complicated by their friend Tim, and Savannah eventually dumps John to marry Tim. Troubled white couples need regular infusions of trouble to keep things interesting, though, so Tim quickly comes down with the cancer. John decides to sell the super-valuable coin collection he inherited and buy treatment for his romantic rival. Tim lives, and John walks away with that sweet fuzzy sense of self-satisfaction to keep him warm at night and have sex with him.

Wait, no. That's what happens in the book version. Studio execs decided at the last minute that they didn't like Channing Tatum not ending up with the girl, so a new ending was hurriedly shot explaining that John's hot money injection only allowed Tim to live for an extra two months, after which John and Savannah got back together.

Why It Ruins Everything:

Look, obviously an extra two months of life is far from worthless. You can clean out an entire garage in two months, and we all want to do that before we pass on from this world. But keep in mind that Dear John's whole plot was set up and shot in preparation for the original uplifting ending about John's meaningful sacrifice. So when they attached the new ending, the studio was forced to shove in a voice-over that implied that Tim dying young of cancer was just as equally happy and awesome for all involved:

Uplifting music! Orgasmically satisfied voice-over! Wistfully happy gaze! Some Big Pharma exec got a new ruby-studded yacht out of John's one valuable possession and Tim died anyway, but we should still weep with happiness, because after all, the two more conventionally attractive people in the love triangle ended up together.

Why It Ruins Everything:

A very vocal subset of Harry Potter fandom is still a little too upset that Harry ultimately ended up with Ginny instead of Hermione, and this scene (which Emma Watson claimed was meant to show Hermione rejecting Harry romantically) just adds more fuel to that fiendfyre. But that's not my problem with this scene.

It's that painfully awkward, fake-casual expression on Harry's face. You just know he is thinking, "Oh man, it's Nick Cave. I bet Hermione loves Nick Cave! This is your in, Potter. You can do this." And then Hermione obviously isn't that into it, so Harry pretends it's all a joke, and Hermione's trying not to hurt his feelings, and then they just keep dancing awkwardly without making eye contact, and you know that if the song ever comes on the radio again they'll both pretend not to hear it and try to change the radio station at the same time. And the brave hero of our seven-book series is made to look like a guy who's too terrified to ask a girl out directly and is forced to go for the old "I was just joke asking you to dance" defense.

If you're lucky enough to have been off making a nice sandwich while that scene played out, here's the recap: A group of unwise teenagers unknowingly release a bunch of demonic forces while staying in a deep-woods cabin. Soon after, one of the teenagers, Cheryl, wanders out into the forest, where she is stalked by some possessed trees, and then ... well, there's no good way for a comedy site to describe a rape scene, so here's a picture of something lighthearted instead.

More like NosPURRatu, am I right?

Why It Ruins Everything:

Genuinely shocking scenes, including rape and murder, do have their place in movies. Recently I saw a really good Canadian movie called The Wild Hunt that contains an incredibly violent scene that sort of comes out of nowhere. So when I'm recommending the film to one of my friends, or to the piles of stuffed animals that serve as my friends, I'll sometimes add a little warning along the lines of "Oh yeah, I should warn you, there is this one really violent scene," and then I explain that I believe the scene is necessary to the film because real-life violence is really shocking and horrible, and movies sometimes have a responsibility to show its consequences.

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They usually understand.

But how do you attempt to explain to your friend who somehow hasn't seen The Evil Dead why the movie you're recommending has a tree-rape scene? Does tree rape contain some sort of deep metaphysical commentary about mankind and nature and shrubbery? Is there an underreported problem with tree rape in our society, and this movie wants us all to finally wake up and talk about? Or is it just in there because they had five minutes of empty screen time, and what else are you going to do with that besides add in some dendro-violation?

So instead of attempting to justify the non-consensual arboreal loving in The Evil Dead to your friend, you have to say something like: "Oh, and by the way, there's also a small amount of tree rape," and then your friend looks at you awkwardly, and you look at them, and then one of you clears your throat, and then they ask, "What about the 2013 remake version? Does that also contain non-consensual sex between woman and shrub?" and you reply, "Yes, it does. I guess the filmmakers decided that the ravishment-by-sapling was just too important to leave out," and then both of you take very long sips of your drinks while staring off into the distance.

C. Coville has a Twitter here and a Tumblr here.