"Frozen Heart" is a song from the 2013 Disney animated film Frozen, with music and lyrics by Kristen-Anderson Lopez and Robert Lopez and performed in the film's prologue by a group of icemen.

The Lopez songwriting duo explained that the song "has origins in a type of song used in past Disney films, like the 'Song of the Roustabouts' from Dumbo and 'Fathoms Below' from The Little Mermaid". Kristen said, "I guess we were in a meeting, and I kept saying: ‘if we could just have a song which basically said the ice is beautiful and dangerous and set up a little mystery'", while Robert added that the "masculine energy of the song establishes the expansiveness of the story". He said, "I think that’s why 'Fathoms Below' is in The Little Mermaid. It’s telling the boys this is going to be a story with songs, but there’s going to be something in it for everyone... It’s not just a princess movie. And Frozen isn't just a princess movie. It’s got a lot of action and fun and entertainment and stuff like that, and 'Frozen Heart' kind of tells you there’s going to be some violence in this story."From Director wrote, "The ‘Frozen Heart’ sequence plays like a fairy tale prophecy – a small story that brings ill tidings – and it’s interesting to note that early drafts of the screenplay included a more explicit prophecy, hints of which can be heard in the song ‘Spring Pageant’ on the Deluxe Edition of the soundtrack album. The decision to drop this prophecy in favour of something less direct is one of a number of smart moves made by screenwriter and co-director Jennifer Lee."

The song is sung by a group of ice harvesters who are cutting blocks of ice from a frozen lake. Throughout the song, Kristoff and his pet reindeer Sven try to join the adult harvesters, but are constantly shut out, and at the conclusion, try their best to emulate the harvesters. The harvesters pile the ice onto a massive horse-drawn ice sled, then ride off, under a night sky lit up by the Northern lights. The beat is supplied by the cutting noise as their saws cut through the ice, and gradually picks up as the song progresses. Many of the lyrics supplied throughout the song foreshadow things to come in the movie, especially in regard to Anna's and Elsa's actions. For instance, the concluding line "beware the frozen heart” is intriguingly ambiguous on just who should beware: those who know the person with a frozen heart (Elsa), or the person suffering from a frozen heart themselves (Anna).

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