The action movie Argylle is based on a book series by author Elly Conway, but there are questions about how many books exist and which one the movie is based on. The 2024 film stars Bryce Dallas Howard as Elly Conway and Henry Cavill as the titular agent Argylle, with Matthew Vaughn stepping behind the camera to direct a new spy franchise after Kingsman. Argylle's PG-13 rating takes a meta approach to the spy novel adaptation by incorporating the author's life into the globe-trotting, world-saving adventure.
https://screenrant.com/argylle-books-how-many-movie-based-on/