Blue (Billie Eilish song)

"Blue" is a song by American singer-songwriter Billie Eilish and the closer from her third studio album, Hit Me Hard and Soft (2024). It was released on May 17, 2024.

Background and release
The song resurrects two songs that she had previously written, "True Blue" and "Born Blue". "True Blue" was one of the first songs she and Finneas had ever written, after "Ocean Eyes", which she performed along with that song in some of her earliest performances. In February 2022, the song leaked online and became viral on TikTok, leading Eilish to reconnect it realizing that she wanted to complete it and release a finalized version.

"Born Blue" was a song that they started writing for Happier Than Ever (2021), even putting it on an early version of the tracklist, but only wrote a few lines and never finished. They decided to rewrite and combine the two songs to reflect how they felt while writing this album and retitling it to simply "Blue".

Music and lyrics
The song starts with an ethereal tone, discussing feelings of sadness and heartbreak as well as referencing every song in the album, and then moves into a dark section with her voice being distorted to a deeper octave.

The melody is used as a leitmotif throughout the album to tie the themes together and make the album feel more cohesive. The melody can be heard in the tracks "Skinny", "The Greatest", and the outro to "Bittersuite" leading into the beginning of this song.

The song ends with the line "But when can I hear the next one", which has led to speculation that this was hinting towards a sister project or sequel to Hit Me Hard and Soft.