Since its release, Agent Kim Reactivated has become one of the year’s hottest K-dramas, debuting at No. 1 on Netflix’s non-English TV chart with 10.5 million views. Leading the action is So Ji-sub, who plays an ordinary single father hiding a dangerous past. But there is much more to the veteran star than his brooding screen presence. From competitive swimming to an unexpected rap career, here are five things to know about him

He spent 11 years training as a competitive swimmer

Photo: Instagram @soganzi_51

Long before becoming a K-drama icon, So was pursuing a very different path in the pool. He trained as a competitive swimmer for 11 years, played water polo during his school days and competed at national level, even winning gold in a team event at the National Junior Sports Festival. His parents had initially encouraged him to take up swimming because he was physically frail as a child. That athletic foundation has certainly served him well in recent action-heavy projects such as Mercy for None (2025) and Agent Kim Reactivated (2026).

His love of hip-hop unexpectedly launched his career

Photo: Instagram @soganzi_51

So’s entry into entertainment was driven less by dreams of fame than by his love of hip-hop. In 1995, the devoted fan of South Korean hip-hop duo Deux entered a modelling contest for jeans brand Storm after learning that the winner would get to work alongside member Kim Sung-jae, who was then the label’s ambassador. So won the contest and became one of the brand’s models. What began as a chance to meet his musical hero unexpectedly opened the door to television and film.

It took him years to become a leading man

Photo: Instagram @soganzi_51

So’s rise to the top was hardly instant. After moving from modelling into acting in the 1990s, he spent years taking on smaller and supporting television parts before gaining wider recognition with Glass Slippers (2002). His career truly took off in 2004, when What Happened in Bali raised his profile and the tragic melodrama I’m Sorry, I Love You transformed him into a major Hallyu star. The latter also showcased the mix of toughness and vulnerability that would become central to his appeal.

He has also built a career as a rapper

Photo: Instagram @soganzi_51

Acting may be his main profession, but So has never left his love of hip-hop behind. Over the years, he has released soundtrack songs, singles and albums, initially recording under names including G and G-Sonic. His musical projects range from the autobiographical “18 Years”, which looked back on his time in entertainment, to the swaggering 2015 track “So Ganzi”, named after the nickname associated with his effortlessly cool image. It is a surprising creative side that newer drama fans may not expect.

A 51-kilometre trail was named after him

Photo: Instagram @soganzi_51

So’s influence even extends into travel. Inspired by his 2010 photo-essay book, So Ji-sub’s Journey, a walking route bearing his name was created around the scenic DMZ area of Yanggu in Gangwon Province. The trail stretches for 51 kilometres across six courses, passing natural landscapes and locations featured in the book. Its length is no coincidence: 51 is So’s favourite number and also inspired the name of his agency, 51K. Few actors can say their fans can literally follow in their footsteps.

Also see: 5 things to know about Nam Joo-hyuk, the star of Netflix’s "The East Palace"