Song Ji Eun (송지은) (born on May 5, 1990 in Seoul, South Korea. She debuted with Secret (시크릿), a 4-member girl group from TS Entertainment, in October 2009 in South Korea and serves as the main vocalist. In 2009, she released a duet with Fly to the Sky's Hwanhee (환희) entitled Yesterday (어젠). In March 2011, she released a single with label mate, Bang Yong Guk (방용국), entitled “Going Crazy” (미친거니). It reached number one on Gaon, Korea's official chart. She was also briefly part of the cast of KBS's Immortal Song 2.