Yu Oh-seong made his stage debut in 1992, and throughout the mid-1990s, he complemented a career in television with minor roles in film. With his success playing a young gangster in the hit movie Beat (1997), Yu’s face became familiar to a new generation of moviegoers. The year 1999 was somewhat of a breakthrough for Yu, as he took the lead role in Jang Jin’s acclaimed cult comedy The Spy and also starred in Kim Sang-jin’s hugely successful Attack the Gas Station.

Yu’s career reached its peak in the year 2001, however. Appearing as Jang Dong-gun’s co-star in Kwak Kyung-taek’s smash hit Friend, which sold an unprecedented 8 million tickets, Yu won effusive critical praise for his hard-edged performance as a ruthless gangster and enjoyed a tremendous degree of exposure.

This fame would carry over somewhat when he took the lead in director Kwak’s fourth feature Champion, a 1980s-set biopic of boxer Kim Deuk-gu, who dominated the Korean boxing scene until his death after the World Boxing Association lightweight championship in 1982. However, even though Yu was praised for his body makeover and acting skills, the film failed to deliver on the high expectations that preceded it. Later that year, a series of highly public disagreements with Kwak, believed to stem from money problems, made headlines and served to cool some of the public’s interest in the actor.