2016–2020: Rising fame and international breakthrough
Choi first gained international recognition with the blockbuster zombie thriller film Train to Busan, where he played the role of high school baseball player, Yong-guk. Premiering at the 2016 Cannes Film Festival on May 13, the film was a critical and commercial success, going on to gross over $93.1 million worldwide. He followed this up with a short, but memorable role as a truck driver in action-adventure film Okja. This marked his first collaboration with director Bong Joon-ho and featured an international cast, including Tilda Swinton and Paul Dano. Okja was screened in several independent theatres domestically, and released on streaming platform Netflix worldwide.
Choi continued starring in several other films after this, including The Princess and the Matchmaker and Monstrum. In 2018, Choi was cast as a mysterious assassin called the "Nobleman" in the action film The Witch: Part 1. The Subversion. The dark persona of the Nobleman was a shift from the characters Choi usually played. In a press interview, co-star Park Hee-soon remarked that Nobleman could be Choi's once-in-a-lifetime character.
In 2019, Choi reunited with director Bong Joon-ho for the black comedy thriller film Parasite. Choi played the main character Ki-woo, the son of a poor family, who schemes to become employed by a wealthy family by infiltrating their household and posing as unrelated, highly qualified individuals. Choi was first approached by Bong after their first collaboration with Okja in 2016, who told the actor to "stay skinny" to play the character. Parasite premiered at the 2019 Cannes Film Festival on May 21, 2019, where it became the first South Korean film to win the Palme d'Or, and was the first film to win with a unanimous vote since Blue Is the Warmest Colour at the 2013 Festival. Among other numerous accolades, Parasite won a leading four awards at the 92nd Academy Awards. It became the first South Korean film to receive Academy Award recognition, as well as the first film in a language other than English to win Best Picture. The cast also won the award for Outstanding Performance by a Cast in a Motion Picture at the 26th Screen Actors Guild Awards. In addition to his role as Ki-woo in Parasite, Choi performed the end credits song "Soju One Glass," which made the shortlist for the Academy Award for Best Original Song.
