About every plot you can think of has already been used.
I know, that sounds pretty depressing, but it’s true. Pretty much every plotline has been used — not once, but hundreds of time. But really, it’s not as bad as it sounds. The reason these plotlines keep getting used over is because they never get old. Readers relish the “save the world”, “I’m really the daughter of a king!”, “I hate this boy but then I fall in love with him” plots. And honestly, I can read those over and over and over.
BUT, there is a point where it becomes too cliché. So how do you avoid those? Easy. Throw in a twist that will catch your readers, pull them into the story because it wasn’t something they expected. Okay, so let’s say you can’t think of that “amazing twist” to pull your reader in . . . what do you do now? Every story is unique, no matter how clichéd the plot or characters are — because every writer has a different voice and different ideas and thoughts. So, give your characters a lot of individuality, and give the readers everything they love — even if it isn’t the most unique plot, if you write it well enough, your readers will cave and keep on turning the pages.
So, remember: How you write your story is just as important as what you’re writing.