When I heard there was a coming bowdlerization of Ian Fleming's works, that our cultural overlords decided James Bond needed to be sanitized[1] for the dainty modern reader, I decided I'd better read some of these novels for myself before they got butchered.
Casino Royale is the first in the series, and it's well-told. The story is laid out at first indirectly, via intelligence reports and flashbacks; then when the action picks up, the author tells the story in real time. The book is better in some ways than the movie(s), not least because the written James Bond is a more credible character than the movie version[2]. Rather than the Mary Sue we know from the movies, here Bond is believably human: beset by doubts, uncertainties, even unease.
There's one silly deus ex machina event in the story, but it's made up for by an unexpected twist ending. All in all a readable, solidly three-out-of-five stars book. It won't change your life but it passes the time.
[1] Yes, it's true, sadly. The institution that owns the rights to Fleming's work employed "sensitivity readers" to look through and remove anything "offensive."
[2] Unfortunately the movies have permanently altered my internal narrator: my brain plays Sean Connery's voice in my head for all of Bond's dialog. A similar thing happened to me when reading Arnold Schwarzenegger's (unexpectedly interesting) autobiography!