The group RIIZE participated in a drama OST for the first time since their debut. Kakao Entertainment announced that at 6 PM on the 18th, they will release OST Part.4 of the MBC Friday-Saturday drama "21st Century Great Lady," titled "Behind The Shine." "Behind The Shine" is a pop track that blends electric guitar melodies with a dreamy atmosphere, enhanced by the emotional vocals of RIIZE members, raising the song's completeness. The lyrics calmly express unspoken true feelings and evoke the narratives of the drama's protagonists. Lyrics such as "Forgotten emotions pour down slowly" and "I will be here quietly, shining only on you" are said to delicately expand the texture of the romance.

RIIZE is a K-pop boy group that has rapidly expanded its global fandom with powerful performances and a distinct musical identity. Since debut, they have achieved various milestones, including becoming the fastest K-pop boy group to perform at Tokyo Dome in Japan, attracting 420,000 spectators across 21 regions worldwide during their world tour, and being the first K-pop boy group to appear at Lollapalooza South America. Member Anton, the eldest son of Yoon Sang, drew attention even before debut.

Meanwhile, "21st Century Great Lady" is a drama set in the 21st-century constitutional monarchy of South Korea, depicting a romance about two individuals overcoming social status limitations to forge their destinies. It airs every Friday and Saturday at 9:50 PM. In episode 3, which aired on the 17th, the story of the contract marriage between Seong Hee-joo (played by IU) and Prince Ian (played by Byun Woo-seok) was fully developed. The OSTs released so far have been praised for building up the emotional line of the drama.