Before "Lights! Camera! Action!" there is one thing a film must have: a good story. Look to the literary past to see how the earliest stories shape the ones we create today and use that knowledge to look at scripts and storytelling. You may be surprised to discover how cognitive science can shed light on how humans experience stories.
The basic plot of all romantic comedies is essentially the same, so the surprise success of When Harry Met Sally can teach writers volumes about all the other ways you can make a story great. Professor Fletcher demonstrates the subtle ways screenwriters can add naturalistic details to make a predictable story still feel realistic and rewarding.