The 2025 Marvel Movie Thunderbolts Features a South Korean Screenwriter

A Seoul-born, Emmy-winning writer helped craft the new Marvel movie that's set to kickstart summer 

A South Korean talent is taking Marvel into its next phase – literally. 

Marvel fans know the studio organizes its films into phases, and the antihero ensemble Thunderbolts will wrap up Phase Five in May 2025 and set the stage for the start of Phase Six in July. Beyond its place in the MCU timeline, Thunderbolts deepens Marvel’s connection to South Korea as Seoul-born writer/director Lee Sung Jin joins the Marvel family as a writer.

Who is Lee Sung Jin, Marvel’s Thunderbolts writer?

Jin, who spent his childhood between Seoul and the U.S., built an impressive career across several hit TV series. He first gained recognition writing for shows like Silicon Valley, Tuca & Bertie and It's Always Sunny in Philadelphia, but his breakout moment came as the creator and showrunner for Beef, the Netflix hit that won five Emmy Awards in 2024. Lee also made headlines in South Korea recently by writing and directing "Come Back to Me" for BTS leader RM. Now he's breaking ground again as the first South Korean to earn a writing credit on a Marvel film, co-writing Thunderbolts with Joanna Calo (The Bear) and Eric Pearson (Black Widow, Thor: Ragnarok, The Fantastic Four: First Steps). 

Jin’s Marvel debut is part of a larger wave of Asian representation in superhero cinema. Asian writers and directors worked on the 2021 films Shang-Chi and the Legend of the Ten Rings and The Eternals, and Thunderbolts continues Marvel's embrace of diverse perspectives. Jin's background in narrative-driven shows highlights his ability to craft stories that transcend cultural and genre boundaries. This milestone builds on the international acclaim for Korean storytelling, from Squid Game's worldwide success to Parasite's historic Oscar wins.

What to expect from Thunderbolts? The film unites an ensemble of morally ambiguous antiheroes to undertake covert government missions. The reluctant team includes several characters from Black Widow (Florence Pugh as Yelena Belova, David Harbour as Red Guardian and Olga Kurylenko as Tastmasker) and The Falcon and the Winter Soldier (Sebastian Stan as Bucky Barnes and Wyatt Russell as John Walker) in addition to Hannah John-Kamen as Ghost from Ant-Man and the Wasp. On the music front, early previews of the film feature nostalgic alt-rock tracks like The Pixies' "Where Is My Mind?" and the Toadies' "Possum Kingdom."

Will the film itself feature more alt-rock nostalgia? 

That's the kind of question that Sonic Conductors have to answer as they shape the soundscapes of films, TV shows, video games and brands. It's a role devoted to sonic storytelling and character development through the creation and curation of music. 

If you think you have what it takes to master this craft, join our introductory course on sonic conducting, led by the mastermind behind Marvel’s cinematic music. Your journey to become a certified Sonic Conductor starts here!