Actors Park Hae Il and Park Seo Joon are set to share the screen in director Lee Joon Ik’s upcoming film. The production company announced the cast lineup for 'Firefly' (directed by Lee Joon Ik) on August 21, confirming that Park Hae Il, Park Seo Joon, and Choi Dae Hoon have joined the project. 'Firefly' follows a detective who wants to escape the constraints of guilt by association. He travels to Hwayong-myeon after pursuing testimony from an unidentified man, eventually uncovering a long-hidden truth. Lee Joon Ik will direct the film. Known for acclaimed historical and period films such as 'The King and the Clown,' 'Dongju: The Portrait of a Poet,' 'Anarchist from Colony,' and 'The Book of Fish,' Lee has frequently explored characters who endure hardship and confront the circumstances surrounding them. His latest project will also be a period piece, moving between 1974, during South Korea's authoritarian era, and 1950, shortly after the outbreak of the Korean War. The story will follow an incident that remained concealed for 24 years. Park Hae Il will portray Man Seob, a mysterious man who approaches a detective in 1974 and tempts him with the possibility of achieving a major career breakthrough if he travels to Hwayong-myeon. Park Seo Joon will play Joon Kyung, a detective whose career has been stalled because of the guilt-by-association system. Hoping to improve his record, Joon Kyung follows the lead Man Seob gives him, only to gradually move closer to the truth. Choi Dae Hoon will portray Tae Sik, a deputy director of the Korean Central Intelligence Agency. Tae Sik is convinced that everything he does is an act of patriotism, presenting a markedly different side from some of the actor's previous roles. 'Firefly' is scheduled to begin filming on September 27.
Park Hae Il is one of South Korea's most acclaimed film actors, known for taking on complex characters across a wide range of genres. His breakthrough years included appearances in 'Memories of Murder' and 'The Host,' with the latter becoming one of the most successful Korean films of its era. He later starred in films including 'War of the Arrows,' 'Eungyo,' 'The Fortress,' and 'The King's Letters.' His most internationally recognized recent work came in 2022, when he starred opposite Tang Wei in Park Chan Wook's 'Decision to Leave.' He played detective Jang Hae Joon in the acclaimed mystery romance, which competed for the Palme d'Or at the Cannes Film Festival, where director Park Chan Wook won Best Director. That same year, Park Hae Il portrayed Admiral Yi Sun Shin in the historical blockbuster 'Hansan: Rising Dragon.' Park Hae Il has continued to be active in film, with 'The Assassin(s),' directed by Hur Jin Ho and co-starring Yoo Hae Jin and Lee Min Ho, among his upcoming projects. Park Seo Joon, meanwhile, has established himself as one of the most recognizable Korean actors internationally. He rose to prominence through hit dramas including 'Kill Me, Heal Me,' 'She Was Pretty,' 'Hwarang,' 'Fight for My Way,' 'What's Wrong with Secretary Kim?' and 'Itaewon Class.' His performance as Park Sae Roy in 'Itaewon Class' in particular helped expand his global fanbase following the drama's success on Netflix. He has also built an increasingly prominent film career, appearing in 'Midnight Runners,' 'The Divine Fury,' and 'Concrete Utopia.' In 2023, he made his Hollywood debut in Marvel Studios' 'The Marvels,' playing Prince Yan of Aladna. He subsequently returned as Yoon Tae Sang in Netflix's 'Gyeongseong Creature' Season 2 in 2024. His most recent drama credit is JTBC's 'Surely Tomorrow,' which aired in 2025. With Park Hae Il's acclaimed film career and Park Seo Joon's strong international following coming together for Lee Joon Ik's latest period project, 'Firefly' is already drawing attention as one of the more notable Korean films currently in production.
