Yeah, you *must* take care of that issue. The rights. Especially if you plan on doing anything with your screenplay, eventually -- selling it to Hollywood, whatever.
It won't be easy. And it probably won't be cheap. I adapted one of my favorite short stories ("The Ex," by William F. Nolan) a few years back just for fun -- mostly just to see if I could pull it off -- and when it turned out pretty cool I decided to shop it around.
No way could I afford what the author wanted, however. And he was even "giving me a break" since I was just a small-time, one-man operation.
Then again . . . you may encounter an entirely different scenario! I know that Stephen King has sold his short stories to indie filmmakers in the past for as low as a buck! You never know what the author will offer you . . . .
It could go either way. Who knows. But definitely know that you must secure the rights before you do *anything* with this project.
In any event, good luck with it, and have fun!
J.N.
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