So was chosen as a model for jeans brand STORM in 1995,[2] then made his acting debut in the sitcom Three Guys and Three Girls and drama Model. But whereas fellow STORM model Song Seung-heon quickly rose to stardom, So had difficulty raising his profile.[3] He appeared in small roles on television throughout the late 1990s and early 2000s, and started to gain popularity when he was cast as the male second lead in Glass Slippers in 2002.
