On November 1, 2021, a teaser was revealed, containing the phrase "Heroes Are Coming" sparking rumors that JYP Entertainment would be debuting a new group soon. On November 15, Jooyeon was revealed as the band's first member. On November 22, JYP Entertainment released a performance video of Jooyeon, showing him playing the bass guitar. They made their debut on December 6, 2021 with the digital single "Happy Death Day".