His next film, released in early 2004, was also a hit. He also appeared in Once Upon a Time in High School, which portrayed the authoritarian society of the 1970s through a notoriously violent high school. Simultaneously, Kwon’s TV tearjerker Stairway to Heaven won high ratings. The drama eventually screened throughout Asia and helped turn Kwon Sang-woo into a regional star. His career stalled in 2006 when his films of that year failed to produce the level of success of his previous films, but his clout increased in 2010 with the release of the successful Korean film 71: Into the Fire. In 2009, Sang-woo established the cosmetics firm Natural Tears and was the inaugural advertising model for the brand TEARS, named for his nickname “Mr. Tears”, given to him by fans in recognition of his tear-jerking acting in Stairway to Heaven. He also opened the cafe Tea’Us in Myeong-dong, and is the largest shareholder of the resort Ocean Blue Hotel Bali.