History Film / LetMeIn

* ViolentlyProtectiveGirlfriend: Subverted with Abby. At first, she just wants Owen to stand up to his bullies on his own, although she promises him if that doesn't work, she'll defend him. When he does so and the bullies retaliate by attempting to either drown or mutilate him, she literally rips them to shreds.
* WeirdnessCensor. A variant with Owen in regards to Abby's behavior. He certainly notices how odd her behavior is, asking why she doesn't wear shoes in the snow, remarks how odd it is she never appears in daylight nor knows very famous pop culture items like a Rubik's cube. And when he confronts Abby, he immediately asks whether she's a vampire, implying he had already guessed, judging by her behavior. It's simply that Owen's so desperately lonely that he's willing to overlook those traits as long as Abby will be his friend.

* AdaptationalAngstUpgrade: Owen suffers a lot more in this version than Oskar did. He's treated much more poorly by his parents. In this version, his mother is an alcoholic who neglects him while in the Swedish version, they have a loving relationship. While Owen's father doesn't even make a single appearance, his voice is only heard on the phone while he totally ignores that his very distressed, crying son plead with him to listen to him. Whereas his Swedish counterpart, despite heavily implied to be an alcoholic, made the effort to see him every weekend. Also, the bullying he endures is much more brutal and violent than the kind shown in the Swedish version, which was a lot more childish than the abuse inflicted on him in this continuity. Considering how much more [[AdaptationalHeroism innocent and kind]] he is than in other versions, it makes his abuse much harder to watch.

* AdaptationalModesty: The scene where Abby comes into Owen's bed to cuddle with him after Thomas dies. In the original film, Oskar is in his underpants. In the book, he was naked. In this version, he's wearing a pair of pyjamas.

* CrimeOfSelfDefense: When Owen defends himself and hits Kenny hes the one seen being summoned to the prinicipals office to be scolded and castigated, despite the fact there was a teacher who had witnessed Owen being harassed by Kenny and his friends. What makes this doubly unfair is how savagely Kenny bullies Owen with no adult intervening throughout the film.

* DarkSecret: The audience knows that Abby is a vampire the entire time; Owen finds out eventually. Stemming from this, Abby tries to hide the more gruesome aspects of her affliction from her new friend (such as what happens when she enters a house without permission, and what she does while sleeping/recuperating in the bathroom), but Owen deals with each in turn.

* DeathByAdaptation: In the book, Eli only kills Jimmy and Kenny's counterparts but lets the other bullies live. Here, she kills them all.
* DefrostingIceQueen: Abby. In their first few scenes, she's incredibly cold and standoffish to Owen. Her first words to him were that they could never be friends. However, when they bond over their shared love of puzzles, she quickly becomes a lot more friendly towards him. Soon they start dating and even playing together like normal children.

* DidTheyOrDidntThey: Towards the end of the film, Owen sneaks out from his mother's apartment to spend the night with Abby and it's never made clear what precisely they were doing during the entire night. While their relationship is portrayed for the most part, [[PuppyLove as very sweet and innocent]], the scene immediately occurred after Abby and Owen reconciled their relationship before being interrupted by his mother's entrance into the apartment. So while it's rather unlikely they had sex, it's still somewhat ambiguous.
* DisproportionateRetribution: In ''Let Me In'', the bullies try to kill Owen for splitting Kenny's ear, in self defense no less. This is distilled from the book where there was an ongoing series of events to get there, but this is the same level as from the Swedish film.

* EeriePaleSkinnedBrunette: Owen, despite being a normal human boy, is extremely pale. He's actually more pale than Abby, who is undead. This is coupled with the fact in this continuity, he's the one with dark hair and he actually looks more vampiric than Abby does at times.

* TheFaceless: Used to signify that this is principally a tale about childhood ([[NotGrowingUpSucks more or less]]), with adult characters mostly peripheral and often fleeting. Owen's island-like status is emphasized by his absent father only making one scene by telephone, and his mother - a fairly constant presence in the book - appears numerous times yet is ''never once seen properly on camera'': she varies from being a distant figure, a ghostly reflection or obscured by a door, to fully visible yet thrown way out of focus or seen only from the neck down; even a passport-type photo glimpsed in her wallet is crumpled to the point of indistinguishability.
* FirstKiss: Abby kisses Owen on the cheek after he tells her how he stood up to Kenny.

* NonAnswer: Abby gives rather vague or cryptic answers when Owen asks her questions. When Owen asks her what her true age is, she only responds that she's been 12 for a "long time". When Abby tries to tell Owen they can't be boyfriend and girlfriend because "she's not a girl" (i.e. she's a vampire, not a human), Owen understandably gets confused and asks her what that means. Her response is to claim she's "nothing", which backfires on Abby as Owen thinks she's just making excuses to not go out with him and gets upset.
* NonHumanLoverReveal: A puppy love version. When Owen and Abby are cuddling in bed, Abby tells him she's not a girl, as in she's not a human but a vampire, which just confuses Owen. Later when they're in the cellar, Owen finally sees what Abby is when he tries to initiate a friendship pact which causes Abby's HorrorHunger to kick in. She assumes her demonic form and throws herself to the ground to lick Owen's blood off the floor with an elongated tongue, to his horror.

* NothingIsScarier: Abby's slaughter of the bullies. During the entirety of the scenes, the cameras focused on Owen's emaciated back covered in blood, but you can hear what's happening - From the bullies' screams of terror and the sounds of their flesh being ripped apart and thrown into the pool, to Abby's own inhuman roars. Throughout the scene, you can also hear the sound of wings flapping; Abby was never shown to have wings when seen in vampire form, so the audience can only guess what she looks like as she kills the boys. Most disturbingly at the end, when Owen has recovered from his near drowning, Abby's bare feet, drenched in blood appear and she picks him up by his head to look at her. When he does, he looks to be in awe and fear, which could just simply be through the trauma of almost dying. However, Abby's face is never seen once during that entire scene, so ''what exactly'' could Owen be looking at?

** The obvious example is Abby, who is centuries old but stuck in the body of a twelve year old.

* PayEvilUntoEvil: The bullies were in the process of drowning Owen before Abby broke in and killed them. While some gave some very weak protest to Kenny when it became clear he was actually going to kill Owen, they still gleefully went to the pool with the intention of assaulting and torturing Owen. Needless to say, they deserved everything Abby did to them.
* ParentalObliviousness: Owen's mother is completely ignorant of her own son's life. She doesn't notice how horribly he's being abused by bullies, despite the fact he shows up with wounds at their apartment and is obviously miserable and desperately lonely. Notably after Owen's called to the principal's office after defending himself against Kenny, all she can state is that he's "a good boy", never bothering to inquire why exactly her gentle, quiet son would attack someone.
* ParentalNeglect: Neither of Owens' parents give him any attention or consideration, beyond his basic material needs. His father mentions he hasn't seen him in months and in the one scene they walk, he plainly doesn't care or notice that his son is crying. His mother frequently ignores him so she can drink.

* {{Pastiche}}: Reeves cited ''Film/ETTheExtraTerrestrial'' as a stylistic influence on the film.
* {{Prequel}}: The comic ''Let Me In: Crossroads'', which John Ajvide Lindqvist did not want to be made (he unknowingly sold the comic rights.)
* PrettyBoy: Owen has extremely fine features, a very slender build, big blue eyes and full lips. In the director's commentary, Matt Reeves even mentions that Owen's face is "beautiful". Unfortunately, this works against him. Owen's looks coupled with his small statue are what gets him attention from bullies. It's also probably the main reason Kenny calls him a "little girl".

* TheRunaway: By the end of the film, Owen decides to run away with Abby. Considering how horrible his life was in Los Alamos and Owen mentioned how deeply he hated living there and wanted to leave, you can't really blame him.

* SchoolBullyingIsHarmless: Completely averted. School bullying is portrayed as just as seriously as any other form of abuse and it's obvious Owen's traumatized from enduring constant assaults and humiliations every day at school with no authority figure protecting or helping him, to the point he's developing several psychological quirks: he wets himself at age 12, he fantasizes about killing his bullies constantly and it's implied he doesn't eat very much.

* TheFogOfAges: Abby genuinely can't seem to recall her own age. When Owen asks her age, she says 12, "more or less" and later she says she's been "12, for a very long time", implying she's forgotten or lost track of how long she's been alive. That, or she's just being evasive to not scare Owen.
* TheGoodTheBadAndTheEvil:
** The Good. Owen. An innocent, timid, gentle, boy who's victimized by nearly every other force in the film, from the bullies who assault him, to his parents who neglect him.
** The Bad: Abby. While she doesn't derive any pleasure from it and she's required to drink human blood to live, she still kills scores of innocent people throughout the film.
** The Evil: Kenny and the bullies. They torture Owen every day for no reason other than cruelty.
* TheQuietOne: Owen is a very quiet boy. He usually speaks as little as possible, such as when he's summoned to the principal's office for hitting Kenny and, when she's scolding him, he doesn't say a single word in his own defense, despite the fact he's being very unfairly punished for defending himself. Or at the end of the film, when a train conductor speaks to him, he wordlessly presents his ticket to him and only gives a very gentle nod when asked whether Abby's trunk belonged to him. He is more talkative around Abby, so it could be he isn't naturally very silent, it's simply that Abby's the only person he's comfortable around.
* ThereAreNoTherapists: Despite the fact it's obvious Owen has mental health problems (he enacts his murder fantasies in the open courtyard of his apartment complex), no one suggests he should be offered help or someone to talk to.

* TookALevelInBadass: A moderate example with Owen. While he remains a shy, withdrawn, little boy throughout the film, he does become more assertive and ready to defend himself, at Abby's encouragement. In the beginning of the film, he makes no effort to fight back as the bullies hurt him, but halfway through the film, he splits Kenny's ear with a metal pole when Kenny tried to hurt him, and when they ambush him at the pool, his first instinct is to grab his knife.