Recognizing that the film's title functions on both of these levels is important because it reveals how Alfredson deploys common vampire tropes in novel ways which serve to elevate the emotional content of the film, so that the "rules" surrounding vampires become metaphors for the emotional development both characters undergo. Thus, following Hakan's death, Eli goes to Oscar and he invites her into his room at the same moment that she implicitly invites him into her life, revealing to him the first explicit hints that she is something other than a twelve-year-old girl. From this point on, the two work to protect and comfort each other while providing each other with the confidence and companionship they need in order to be happy. Oscar confronts his bullies, and after a period of initial unhappiness, Eli gains a friend who accepts her as a vampire.

Though Eli initially has far more agency and power than Oskar, she is no less isolated, lonely, and anxious about her existence, and the film uses her status as a childlike vampire dependent on an ineffectual adult to mirror Oskar's relationship with his parents and school teachers, all of whom are completely unaware of the bullying he must endure and the crushing loneliness which characterizes his life. Thus, while the two characters begin the film with an apparent distance between them in terms of agency, over the course of the film their lives are revealed to be not that different, at least thematically, if not literally. This similarity is what gives the film its poignancy, because as their relationship develops, Oskar and Eli give each other the necessary support that they have been lacking,...

By examining how the title simultaneously refers to the rule regarding inviting a vampire into one's home and the process by which Oskar and Eli invite each other into their inner lives, revealing their fears and hopes in a way that they cannot do with the adults in their lives. As Oskar lets Eli into his room, Eli lets Oskar into her life, and the two develop a bond which ultimately serves to save their lives, as Oskar rescues Eli from a vengeful townsperson and Eli rescues Oskar from the bullies attempting to drown him. In the end, the film demonstrates the unique brutality and compassion of childhood, and shows how two children, despite their actual ages, can come together to form a bond that defies not only their circumstances, but the audience's assumptions regarding the nature of vampires, violence, and love.
Works Cited

Anderson, John. "A Boy and His Ghoulfriend: Beyond the Genre." Washington Post 07 Nov

2008, n. pag. Print. .

Ebert, Roger. "Let the Right One In." Roger Ebert. Sun Times, 12 Nov 2008. Web. 7 Dec 2011.

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