Season 1s are great, setup, some payoff, a bit of lead into the overarching story. Then season 2 to X. The heroes win and then lose in the final episode, cliffhanger to next season. People get bored. Final season is announced and they wrap up the show.
Not sure about the show, but Margaret Atwood has been at pains to point out that pretty much everything in her books has a real life precedent (albeit in different places at different times).
Child appropriations under the military juntas in Latin America, for one.