When you hunt for a story, focus on the concept you need to illustrate and ask someone to help you come up with ideas.  Once you have found one watch or read the scene again closely, pull out descriptions that set the scene in context for people who are not familiar with the big story.  And tell it with sensory details (George Clooney in drag) that conjure strong images.   Choosing a well-known book or movie takes advantage of all the hard work the author or director did stimulating senses and capturing attention.  Make the story yours by adapting the format and style, including the details of how you came across this story, or by elaborating on what this story has meant to you and why you are sharing it.