Basic plot: The world is taken over by bad guys and the good guys are oppressed. This has been used in about a million movies and novels. Road Warrior, Star Wars, Running Man, 1984, A Clockwork Orange, and on and on.
How is it portrayed? What is the author’s intention?
Compare two books: Battlefield Earth by L. Ron Hubbard and The Hunger Games by Susan Collins. Both runaway best sellers. I enjoyed them both. The good guys in both stories had to fight against overwhelming odds and saved humanity. Both deal in the heroic action of their protagonists.
What message did the author convey?
Battlefield Earth is an adrenaline rush of excitement. If you had to distill a theme from it, it would be that a person can do great things, that he is in control of his destiny. The protagonist, Johnny Tyler, is even gracious to the enemy after they are defeated.
The Hunger Games is moody. The lead character, Katniss is often one step from a breakdown. At the end of the book, it is ambiguous whether she saved the world or just passed it on to new dictators who hopefully were marginally better than those just deposed. Even in victory, Katniss is not happy and probably never will be.
Battlefield Earth was written to inspire people, to tell them that their lives were important and that they could do great things. The Hunger Games targeted young women from 15 to 18 who might have been struggling with their own lives and related to the brooding Katniss.
There is room for the visions of both books in our literary canon. My opinion is that we need a more optimistic view from out fiction, especially in these times and particularly for our young people.