[1][2] The ensemble cast also includes Josh O'Connor, Glenn Close, Josh Brolin, Mila Kunis, Jeremy Renner, Kerry Washington, Andrew Scott, Cailee Spaeny, Daryl McCormack, and Thomas Haden Church.

Before the release of Knives Out (2019), Rian Johnson said he would like to create sequels with Benoit Blanc investigating further mysteries, and already had an idea for a new film.

[6] By January 2023, Johnson confirmed that he had started writing the script for the third film, stating that it will be tonally and thematically different from the previous installments.

[8] In October 2023, following the resolution of the 2023 Writers Guild of America strike, Johnson announced that he had started working on the script for the third movie.

[11] In May 2024, Josh O'Connor, Cailee Spaeny, Andrew Scott, Kerry Washington, Glenn Close, Jeremy Renner, Mila Kunis, and Daryl McCormack joined the main cast.