Kevin Penkin is an Australian composer of Japanese animation and video game soundtracks, recognized for his distinct orchestral and electronic musical identity. Born in 1992 and raised in Perth, Penkin began his career after studying composition and music technology at the Western Australian Academy of Performing Arts at Edith Cowan University, later earning a master's degree in film composition from the Royal College of Music in London. His early career was notably advanced by a connection with legendary game composer Nobuo Uematsu, who invited Penkin to work on the game Jyuzaengi Engetsu Sangokuden after hearing his portfolio. Penkin has since received a BAFTA nomination for his work on the game Florence and won multiple Crunchyroll Anime Awards for Best Score for his work on Made in Abyss and Tower of God.

Arnór Dan Arnarson, known professionally as Arnór Dan, is an Icelandic singer-songwriter born in Reykjavík in 1985. He is best known as the lead vocalist of the progressive rock band Agent Fresco, which he helped found in 2008. He has also maintained a significant collaborative relationship with Icelandic multi-instrumentalist Ólafur Arnalds, contributing vocals to Arnalds' 2013 album For Now I Am Winter and to tracks for the British television series Broadchurch. In 2016, he was named Male Vocalist of the Year at the Icelandic Music Awards. His work within anime began in 2014 when he performed several songs on the soundtrack for the series Terror in Resonance.

The collaboration between Kevin Penkin and Arnór Dan is most prominently documented in the context of the second season of the anime Made in Abyss, subtitled The Golden City of the Scorching Sun. Penkin composed the complete original soundtrack for the series, which was released as Made In Abyss Original Soundtrack 3 by Kadokawa on October 26, 2022. Arnór Dan is featured as a vocalist on two tracks from this album. The track "Tomorrowland" lists Arnór Dan as the performer and lyricist, and he receives a similar credit as the featured performer and lyricist on the track "Gravity". The song "Gravity" appears as the fifteenth track on the first disc of the two-disc album. This track is a vocal piece characterized by a slow tempo and a melancholic, low-energy atmosphere.

Beyond this specific collaboration, Penkin's broader body of work for anime includes acclaimed scores for the first season of Made in Abyss, The Rising of the Shield Hero, Tower of God, and The Apothecary Diaries. His scores frequently feature guest vocalists; past collaborators on the Made in Abyss series include Takeshi Saito, Raj Ramayya, and Uyanga Bold. Penkin's musical identity blends orchestral arrangements recorded with ensembles like the Sydney Scoring Orchestra with electronic and ambient textures, creating a style that has become influential within the anime industry.