O.O.O was formed in South Korea in 2011 by vocalist and guitarist Ga Geunwoo, guitarist Gong Seokjun, and drummer Goh Doyeon, all former art students. The trio debuted with the single "On A Rainy Daye" in 2014, showcasing their modern rock sound. In 2016 they released the EP HOME, followed by another one GARDEN in 2017 and a full album PLAYGROUND in 2018, each receiving critical attention for its melodic guitar work and introspective lyrics. The band toured across the Korean indie circuit, signing with an independent label that supported their releases. O.O.O’s music has appeared on several indie charts, and PLAYGROUND earned a nomination for Best Rock Album at the 2019 Korean Music Awards, marking a significant milestone in their career. The track "Line of us" on their single album Jose, released on November 23, 2025, entered Melon's Top 500 Melon domestic chart at rank 22 the next day.
