Reading Inside Story, The Power of the Transformational Arc, by Dara Marks, who spoke at a screenwriting workshop he recently attended. He said he has lots of books on screenwriting, but this one is the best one he's read--it's easy to read and has good information on character development. The last screenplay he read was The Fugitive, by Roy Huggins, David Twohy, and Jeb Stuart.
Right now he's working on a screenplay about a man who must decide between quitting his job and doing what he really wants to do--a dilemma most of us face every day. He also has a science fiction and a few other screenplays in the drawer.