One of the more famous examples happened to well-known author and activist Hellen Keller. Keller, who became blind and deaf while still a baby, wrote a story when she was 12 years old entitled “The Frost King”.

Later, it was discovered that her story strongly resembled a similar story by Margaret Canby’s “The Frost Fairies”. Keller insisted she had no conscious memory of ever reading Canby’s story but concedes that maybe it was read to her when she was younger and somehow she retained pieces of the plot in the back of her mind.

Another example came from Alex Haley’s “Roots” published in 1976. Haley was accused of plagiarism by a man named Harold Courlander, who wrote a novel entitled “The African”. A court examined the two works and determined that the similarities between them were more than just a coincidence. Eventually Haley settled with Courlander, all the while insisting that “Roots” was his own, original creation.

Famous Cases of Plagiarism - Lessons to Learn (from the website of a plagarism detection tool)

Tropes are just tools. Writers understand tropes and use them to control audience expectations either by using them straight or by subverting them, to convey things to the audience quickly without saying them.
Human beings are natural pattern-seekers and storytellers. We make use of stories to convey truths, examine and exchange ideas, speculate on the future and discuss consequences. To do this, we must have a basis for our discussion, a new language to show us what we are looking at today. So our storytellers use tropes to let us know what things about reality we should put aside and what parts of fiction we should take up.


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If your favorite shows have long lists of tropes associated with them, well, so do everybody's. A show featuring an Action Girl or showing a character kicking the dog is not a bad thing; the former is merely a reasonable type of character (badass character who is female) and the latter is a character action that happens plenty in Real Life.
Also, consider the size and/or complexity of the work. A four-part TV miniseries, 3 hour movie, or 700 page novel is going to have more tropes than a standard length work. As would very large multipart works such as a 200 episode series, 5 movie franchise, or a book trilogy. A novel with a complicated, intricate plot will also use many more tropes than a simpler story. Consider the analogy of a house: a 7-bedroom house obviously uses more materials than a two bedroom one. Constructing a floor of a building as a twisty maze uses much more materials than a floor with just a couple of corridors, etc. Tropes are the cement that holds together the words (water) and concepts (aggregate) used to create the story (concrete).


There is nothing new under the sun. Including that very statement. And the book from which it comes. Completely ignoring the possibility that one's favorite show just might not be hewn from the very essence of the universe by Thor himself and placed in the periodic table under Or for "Originalium" doesn't change the fact that it wasn't. And acknowledging that it isn't should not lessen its appeal, either.
Every story is influenced by what came before it — and storytellers (e.g., writers, directors, actors) are bound to show that influence, intentionally or not, in the process of telling. Just because something's been used before doesn't mean it's a Cliché; and stories often gain something by having ties to other works. That said, there certainly is such thing as too derivative, but there's a difference between playing a trope straight and utter Cliché Storm (and even those aren't necessarily bad).
It's impossible to write something completely and utterly without tropes, anyway, so stop trying. TVtropes - "Tropes are tools"