"Through the Night" (Hangul: 밤편지; RR: Bampyeonji; lit. Night letter) is a song recorded by South Korean singer IU for her fourth studio album Palette (2017). Written and composed by IU, and produced by Je-Hwi Kim, and Hee-Won Kim, the song served as her lead single, released on March 24, 2017. Marking her return to music, the stripped-down song offers a sharp departure from her previous single Twenty-Three.

“Through the Night” debuted at number two on the Gaon Digital Chart, before achieving its number one status the week after. It became IU’s 14th number one single in South Korea, enabling her to extend her lead at the time over popular idol groups Big Bang, Sistar, and 2NE1, which each had nine. The song won two awards at music shows and has been nominated for numerous year end awards.

The song’s accompanying music video was directed by Lee Rae-kyung, and it currently is the second most viewed Korean music video by a female soloist on YouTube in 2017, after IU’s own song from the same album, "Palette".

While the album itself was teased as early as February, IU began releasing teasers for the song the same week of its release. The first set of images were revealed Monday, March 20th, which revealed the singer-songwriter dressed in traditional Korean clothing Two days before the song’s release, a teaser video was released featuring snippets of IU’s voice. IU herself was seen in the video in a traditional Korean home wearing some of the same outfits from the teaser images. The song and accompanying music video were released the Friday of March 24th, 2017 at 6pm KST.

“Through the Night” is a minimalist ballad song, which most prominently emphasize the singer’s vocals over the instrumentation. IU’s vocals are described as being warm, and yet apprehensive in this love song which delves into the acoustic and folk genres. The track was written and composed by IU, while it was produced by Je-Hwi Kim, and Hee-Won Kim. It runs for four minutes and thirteen seconds and is performed in the key of A flat. The tempo runs at 79 beats per minute and is set in a 4/4 time signature.

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