Yeon Sang-ho expands cinematic universe with gripping family mystery 'Paradise Lost'

Fresh off critical acclaim in Toronto, director Yeon Sang-ho’s latest film "Paradise Lost" — a project rooted in a story passed down by his mother — is making its way to home.

The psychological thriller centers on So-young (Kim Hyun-joo), a grieving mother whose world is upended when her son, Sun-woo (Bae Hyeon-seong), whom she presumed dead after a camping bus went missing nine years ago, miraculously reappears.

The film made its world premiere on Sept. 13 at the 51st Toronto International Film Festival. Following last year's "The Ugly," this marks Yeon's second consecutive year being officially invited to the festival's Special Presentations section — further expanding the ever-growing "Yeon-iverse."

Based on the novel "Black Inferno," the plot follows So-young as she relies on an artificial intelligence program called "Children of Paradise" to interact with a digital avatar of her young son just to get through each day. Then comes the shock: Sun-woo returns home alive. While the public erupts over his miracle survival, So-young is gripped by a growing dread. Covered in scars, possessing a chilling gaze and bearing no resemblance to the innocent boy she once knew, the young man standing before her feels like a complete stranger.

Yeon said the idea for the film all began with a short story written by his mother.

"My mother asked if coming up with screenplays was difficult, and I told her that anyone can write if they have a story to share," Yeon said during a press conference at CGV Yongsan I'Park Mall in Seoul on Friday. "When I returned the following holiday, she handed me a notebook with a three-page story she had written herself. That original draft became 'Paradise Lost.'"

Much like his 2025 feature "The Ugly," Yeon described "Paradise Lost" as a low-budget passion project fueled by a desire for total artistic control.

"Financing my own work gives me the freedom to experiment without the burden of turning a profit for corporate backers," he explained. "It feels almost like a student club activity, and that creative liberty is addicting."

Speaking on the casting process, the director revealed that casting Kim alongside Bae was intentional to avoid conventional dynamic tropes. "I needed more than a typical mother-son relationship; there had to be a complex underlying tension between them," he said.

The production marks Yeon’s fourth project with Kim. The director lauded her ability to shift into high-intensity scenes. "Watching her act is like watching an F1 driver — the moment she steps on the gas, she locks in at full speed with incredible intensity," he said.

Kim acknowledged the demands of the role while expressing gratitude for the opportunity to expand her acting range. "An actor can only push new boundaries if they are given the chance. I am deeply grateful to the director for recognizing what I wanted to explore as an actor and giving me the platform to unpack those deeper emotional layers."

The film marks the first leading feature role for Bae, who recently gained recognition in the JTBC drama "Family by Choice" (2024). Bae admitted feeling substantial pressure stepping into his first major film lead, noting the responsibility of presenting a distinct new image to audiences.

Both Yeon and Kim praised Bae’s sharp screen presence. Kim noted that while Bae is gentle off-camera, his demeanor shifts dramatically in character. "During one scene, locking eyes with him brought me to tears," Kim shared. Yeon similarly highlighted Bae’s expressive look, citing a raw, instinctive quality in his eyes that adds to the film's tension.

Known for such hit projects as the films "Train to Busan" and "The Ugly," along with the Netflix series "Hellbound," Yeon’s latest work promises his signature high-immersion storytelling and psychological depth. Yeon expressed strong confidence in the project, stating the film showcases "the peak of actor Kim’s 30-year career alongside a completely unseen side of actor Bae."

"Paradise Lost" will make its debut in the Gala Presentation section at the 31st Busan International Film Festival on Oct. 9, followed by its nationwide theatrical release on Oct. 21.