" A logline is a one-or two-sentence distillation of a story. It usually tells us who the protagonist is, what challenge or conflict or situation the protagonist will confront, and when the story takes place if it isn’t set in the present. Used by writers to keep themselves on track or as a marketing tool to pique the interest of a producer or an audience, a logline is not meant to tell the whole story or to reveal a surprise ending. A logline for Jaws could be, “A shark threatens a seaside town on the Fourth of July weekend.” A logline for Little Miss Sunshine might be, “In spite of innumerable obstacles, Olive and her family are determined to get to the Little Miss Sunshine pageant on time. "

― Linda Seger , Making a Good Script Great