There is no shortage of great ideas -- the writer's CRAFT is the difference. Often the craft is finding a new way to tell a familiar story; or a familiar way to tell a familiar story -- as a friend who writes romance novels says, "I give my readers the stories they expect."
But there is also the unexpected.
How do you give Shakespeare -- specifically "Hamlet" -- a twist? Tom Stoppard does it with Rosencrantz and Guildenstern are Dead. A line near the end of "Hamlet" triggers the entire play, first produced in 1966 (and made into a film in 1990). This play is interwoven with scenes from Hamlet; often with the two protagonists looking on in amazement at the action on the stage. I often taught the two plays together and one of my students said, "That Stoppard guy, he's just samplin' Shakespeare, right?"