In celebration of their 100th episode next month, KBS's "Yoo Hee Yeol's Sketchbook" will be holding a four week-long special! Since SBS's "Chocolate" concluded its run earlier this year, "Sketchbook" is one of the few public broadcast programs left that caters to showcasing authentic music. By using their 100th episode as a milestone, the program has created a series of specials that aim to show the past and future of Korean pop music. The series kicked off on May 13th with the first concept, "The Producer". Some of the legendary producers and composers of Korea like Kim Hyung Suk, Jo Young Soo, Brave Brothers, Sung Shi Kyung, Kim Johan, Na Yoon Kwon, and Kim Jinho guested on the program this day. Producers were also asked to invite singers of their own choice to perform on the show, to which Brave Brothers invited SISTAR and After School. The episode scheduled to air on the 20th will include a line-up of singers from minor labels, followed by an OST-themed special on the 27th. The day of the show's 100th episode, the 3rd, will spotlight session men. Check out some of the performances below! -- < Sung Shi Kyung - "The Road to Me" > -- < Na Yoon Kwon - "Expectation" > -- < After School - "Ah" + "Diva" + "Because of You" > -- < SISTAR - "Push Push" + "How Dare You" > -- < SISTAR19 - "Ma Boy" > -- Source + Photos: PD Journal