After doing small roles on television starting 2005, Song gained fame in 2007 when he starred in "Golden Bride", a drama about an inter-cultural marriage between an elite Korean man (Song) and a young Vietnamese woman (played by Lee Young-ah). He followed that with leading roles in the revenge court thriller "The Scales of Providence", and the post-war film "Once Upon a Time in Seoul". The latter, titled "Boys Don't Cry" in Korean, is about two orphaned friends (played by Song and Lee Wan) who become involved in the black market to escape poverty. Song had to lose 7 kilograms (15.4 pounds) and shave his head for his role. In 2009 he was cast as the antagonist in the Kwon Sang-woo starrer "Cinderella Man", a "Prince and the Pauper" tale set in the world of fashion merchandising, which drew lackluster ratings.