Walking Dead finished on a high with over 15 million viewers this past week. That's the best for the series season finale yet. The show's run has been a hall mark of success, from its quiet opening to its hammer pounding the ratings.
It helps that its a good show. If you haven't watched, its on Netflix. Catch up. You'll be glad you did.
I think a huge appeal is the struggle these characters have in the post apocalypse world. From finding food and water, shelter, to fighting others who seek the same resources. Its the first time we've seen it played out over time.
And there are always zombies, that helps too!