Super Junior-K.R.Y. is a K-pop group and the first sub-unit of the popular boy band Super Junior, formed in 2006. Made up of the main vocalists Yesung, Ryeowook, and Kyuhyun, the group debuted with their performances of the songs "The Night Chicago Died" and "The One I Love" for the soundtrack to the drama Hyena. Their first live performance occurred on November 5, 2006, on the music program Music Bank. In 2010, Super Junior-K.R.Y. embarked on their first concert tour across Asia, spanning multiple cities and attracting over 22,000 attendees. Their popularity continued to surge, and by the time of their 2012 special winter concert in Yokohama, their tickets were selling out in mere seconds. Their first major milestone in Japan was the release of the single "Promise You" in January 2013, which soared to number 2 on Oricon's daily singles chart and sold over 69,000 copies in its first week. However, their activities were paused when Yesung began his mandatory military service in 2013. In 2015, following Yesung's discharge, they announced the release of their second Japanese single "Join Hands." In 2019, after all members completed their military services, Super Junior-K.R.Y. made a comeback, performing at the Jeddah Season Festival and various other events. In 2020, they released their first Korean EP since their formation, titled When We Were Us, as part of Super Junior's 15th anniversary celebrations. The extended play peaked at Number 1 in South Korea and was followed by the Japanese single "Traveler," which also topped the Oricon Daily Singles Chart.