The film's source novelist is Robert Littell who has been a journalist and novelist who specializes in espionage novels that frequently are set around the spy world of the CIA and the former Soviet Union. He wrote the screenplay for the original movie of 'The Amateur' then wrote the novel of the same name afterwards. The book has a slightly different title, it being "The Amateur: A Novel of Revenge (1981)". The original 'Amateur' movie was his first film & TV credit.
The house of Charlie and Sarah (Rami Malek and Rachel Brosnahan) is the same house in the Black Mirror episode "Beyond the Sea" (S06E03) with Aaron Paul and Kate Mara.
Filming was suspended in July 2023 due to the SAG-AFTRA strike. Filming resumed by December 2023.
Marthe Keller plays the Florist in this film. She also starred in the 1981 version of the film, playing the character Elisabeth.
The casting of Rami Malek in the lead role was influenced by the actor having played the Bond villain (Safin) in the last 007 film 'No Time to Die' (2021)
Marthe Keller: The actress, who played Elisabeth in the original movie, is seen briefly as a florist.