The series is based on the story of the Captain, a
North Vietnam plant in the
South Vietnam army. He is forced to flee to the United States with his general near the end of the
Vietnam War. While living within a community of South Vietnamese refugees, he continues to secretly spy on the community and report back to the
Viet Cong, struggling between his original loyalties and his new life.
In April 2021, Viet Thanh Nguyen announced that his novel The Sympathizer had been optioned by
A24 to be adapted into a television series with
Park Chan-wook directing.
Rhombus Media is also involved in the production. In July,
HBO ordered the series from A24, and
Robert Downey Jr. joined the project in a producer and co-star role. The state of California awarded the production over $17.4 million in tax credits ensuring significant production would take place in state.Marc Munden and
Fernando Meirelles were also hired to direct some episodes of the series.
Casting director Jennifer Venditti opened a worldwide casting call in order to find a main cast of Vietnamese descent, ultimately hiring
Hoa Xuande, Fred Nguyen Khan, Toan Le, Vy Le, and Alan Trong. Recurring roles for
Kieu Chinh, and
Nguyen Cao Ky Duyen were also announced in November 2022, and Downey was portraying several supporting antagonistic roles representing the American establishment. In May 2023, Scott Ly and
Marine Delterme joined the cast, in recurring roles.
Filming took place in
Los Angeles and
Thailand. Downey shaved his head for the series in order to save time required to use a bald cap for each of the various characters he portrayed. A significant portion of Downey's performance was also improvised.
The series will air on
HBO and be available to stream on
Max in 2024.