"Love Is an Open Door" is a song written by Kristen Anderson-Lopez and Robert Lopez for Walt Disney Animation Studios's 53rd animated feature film Frozen (2013). Performed by Kristen Bell and Santino Fontana as Anna and Prince Hans respectively, "Love Is an Open Door" is a romantic duet which takes place during the first act of the film, when Anna meets Hans during the reception of her sister Elsa's coronation. The song was intended by Lopez and Anderson-Lopez to "feel like the perfect first date", inspired by the date depicted in the film The Karate Kid (1984).

The notion of a song that doubled up as a romantic duet and the villain song came to fruition after the writers decided to turn Elsa into a tragic hero rather than a villain, leaving the door open for Hans to become the villain of the film. The first song written for the film, "You're You", was cut from the film, due to Hans interrupting Anna in the song, an act which would have lessened Hans' reveal as a villain later in the film. "Love Is an Open Door" was eventually also recorded by Demi Lovato, but never released.

The song is inspired by the date depicted in the film The Karate Kid (1984), and it is "intended to feel like the perfect first date", according to the songwriters. The line about finishing "each other's sandwiches" originally had nothing to do with the television show Arrested Development. Anderson-Lopez explained she was eating a sandwich at the time she wrote the line, but had not seen the show, and it was not until Lopez's brother pointed out the connection that they realized audience members might hear it as an Arrested Development reference. They tried pitching a couple of alternate versions to Disney, but the line about sandwiches stayed in.

The song is written as an apparent love duet sung by Princess Anna of Arendelle with Prince Hans of the Southern Isles. Anna opens the song by explaining to Hans her loneliness by being shut out from Elsa for years, with Hans promising to never shut her out. As the night goes on, the two gradually find themselves sharing a lot in common, and towards the end of the night, Hans proposes to Anna, and she accepts.

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