(from the first letter of the members' stage names)[3] released two original soundtrack titled "The Night Chicago Died" and "The One I Love" for the tvN drama Hyena.

The tour commenced in Tokyo in August 2010 and continued onto Kobe, Taipei, Fukuoka, Seoul, and concluding in Nanjing, China.

[7] Super Junior members Donghae, Sungmin and Heechul made special guest appearances at the Seoul concerts, as well as labelmates Shinee and TRAX.

Special Winter Concert 2012 was held in Yokohama on November 19–21 with 15,000 fans in the audience.

released some tracks and a teaser video from their upcoming Japanese single "Promise You" for the first time at the concerts.

They continued their activities as a trio with held Japanese tour, starting in Yokohama on June 2–3 and had 11 total performances in arenas in Kobe, Fukuoka and Nagoya.

[17] In June 2015, the trio announced will be released their second Japanese single titled "Join Hands" on 5 August 2015.

[26] The EP is part of a chain of activities to celebrate 15 years since formation for Super Junior, from 2005 till 2020.