She became part of the "Dream Team Girl Group" for Samsung's Anycall called "4 Tomorrow". Their first digital single "Dugeunduguen Tomorrow" (, ""BeatBeat Tomorrow"") was released on October 6, 2009, and the official music video was released on October 12, starring actor Lee Dong Gun, who will also star in each member's individual drama version of the video. Seungyeon's version was released on October 26, 2009.