The Robber Fly colony of Monster Rats have seen the mainstay of their insurrection against the townsfolk of Shin Sekai Yori crushed, but is that the end of the matter? As the healthy survivors of that rebellion go on patrol, there's an understandable sense of unease as to what exactly is going on.
As Satoru and Saki join a group of three such survivors, they begin to mull over the reality of what they've just witnessed - is this really the work of a single colony headed by Yakomaru, and why would he wage such an impossible war against mankind? Satoru can only surmise that there is far more to the unfolding situation than this, and his own eyewitness account of another Monster Rat colony's involvement in the raid on there town seems to back this up.
Any such theories have to be put on hold as the group reach a nearby riverside hospital which has clearly been attacked during this uprising, and it doesn't take long for Satoru to discern that they've stumbled slap-bang into the middle of an ambush. The waiting Monster Rats may not be able to contend with a bunch of human users with Powers, but they still have enough wiles to take out one of their opponents, and once inside the hospital the true and terrible extent of what the town is up against slowly comes to light... an impossibility that could threaten them all.
Never mind ethics, provoking thought or turning a mirror on the audience's world, this week's Shin Sekai Yori quickly turned into a session of survival horror - something which it proved to be surprisingly adept at as the tables were turned on our protagonists in a way which currently defies explanation but will surely both prove fascinating and further tie in to questions as to the ultimate fate of Maria. The switch in focus here has ultimately shown itself to be another feather in Shin Sekai Yori's bow, as its second half continues to go from strength to strength even when it isn't at its intellectual peak.