I'm on a bit of a writing hiatus, but have started watching random stuff on Netflix. If I run into something noteworthy, I'll add it to this thread.
To start with, I'm looking at Attack on titan
From wikipedia (http://en.wikipedia.org/wiki/Attack_on_Titan
“The series began in Kodansha'sBessatsu Shōnen Magazine on September 9, 2009, and has been collected into 15 tankōbon volumes as of December 9, 2014. It is set in a world where humanity lives inside cities surrounded by enormous walls as a defense against the Titans, gigantic humanoid creatures who eat humans seemingly without reason. The story initially centers on Eren Yeager, his adopted sister Mikasa Ackerman, and their childhood friend Armin Arlert, who join the military to fight the Titans after <redacted>. However, as the story progresses and the truths about the Titans are slowly revealed to the reader, the main narrative shifts, centering increasingly more around Historia Reiss, one of the top soldiers from the Survey Corps and the youngest child of the ruling family within the walls, of which the long-kept secrets are directly connected to the origin of the Titans and the lost history of the world.”
This series is currently on Netflix Canada (no idea about the US) and is very intense - or at least I found it so. Its difficult to discuss without venturing into spoilers but let’s say s**t gets real, really fast. So far it does not pull punches and thats with me being two episodes in.
I find the premise could easily be adapted into an RPG campaign - choose your era - fantasy/steam-punk/sci-fie - you have humanity trapped inside walls, with an implacable enemy outside. The PCs may need to overcome political resistance to be allowed to sally forth to explore, learn out their foes, gather resources, etc. Perhaps the abandoned remains of prior attempts to settle outside the walls may be found. Maybe another - breached- ring of walls exists outside of the known ones.
In some ways, I attempted something vaguely similar in my Neyanthis world, but not as well paced
Humanity and other nations are relatively small in comparison to the amount of wild lands surroundings, with their expansion knocked back time to time by threats from outside.