Seo Jae-Won (서재원) is a South Korean screenwriter. He was born in South Korea. Seo began gaining recognition in the industry with the drama Family (2012), showcasing his ability to capture complex relationships and heartfelt moments. He expanded his creative reach with Entourage (2016), the Korean adaptation of the hit American series, which offered a sharp, behind-the-scenes look at the entertainment industry.

In 2018, Seo demonstrated his versatility with The Guest, a chilling supernatural thriller that combined exorcism, folklore, and crime in a gripping narrative. His talent for blending genres continued with Bulgasal: Immortal Souls (2021), a fantasy epic exploring themes of revenge, immortality, and fate, further cementing his reputation as a screenwriter unafraid to tackle ambitious and emotionally resonant stories.

Seo Jae-Won’s most recent work, East Palace (2025), continues his trend of genre innovation. The historical-fantasy drama follows a warrior who battles ghosts, a court lady who hears the dead, and a king confronting a deadly curse—blending palace intrigue with supernatural adventure.