Hollywood loves simple stories that are highly visual, so many films started out as comics or graphic novels: Bat Man, The Crow, Sabrina the Teen Age Witch, Men in Black, The League of Extraordinary Gentlemen, etc. etc. Manga, famous for the richness of its illustration, also gives the film industry what it wants, highly visual stories. Manga naturally gets turned into films too: 20th Century Boys, Memories of Nobody, Dragon from Russia, Full Scale of Fear, and many, many more. Indeed, when I went to a Pitch Fest (a pitch fest is when screen writers pitch their ideas for films to producers), a very successful screenwriter told how he could not get anyone to produce his latest script. He hired a graphic artist and turned his script into a graphic novel. A publisher snapped it up, and film producers finding it in bookstores decided to produce the graphic novel as a film.
I found out at that same Pitch Fest that producers don’t want to do films that have “WATER!.” Oceans, rivers, “WATER! “is big trouble to film, apparently. You can’t relie on calm seas. The sea can suddenly turn violent and sink your whole set. Getting rivers to behave so that it doesn’t carry off the actors to where you can’t find them is another sore point. Also all that “WATER!” does bad things to electronic equipment, and films are made with lots of expensive electronic equipment. This was all bad news for me because I had written a script where vampires steal a nuclear submarine. It has “WATER!” oh no! Well,