In January 2020, an HBO six-hour limited series based on the film, with Bong and Adam McKay serving as executive producers, currently in early development, was announced as an upcoming project. Bong has stated that the series, also titled "Parasite", will explore stories "that happen in between the sequences in the film". In February 2020, Mark Ruffalo was rumored to star while Tilda Swinton was confirmed to being cast as the female lead. In February, 2021, Bong announced he had finished one of two scripts he had been working on for the Parasite sequel, having spent the past year working on both scripts simultaneously. He stated that one script is in English and the other in Korean, with no comment on which one he had finished.