On June 20th, 2016 the full moon rises over the Eastern United States and a quarter of the population in the light of that moon transform into werewolves. They in turn, kill about a third of the remaining population in the US. There are no warning signs and many people are caught off guard as they are attacked by strangers in large venues or by their own loved ones at home. The werewolves are vicious and predatory, with a mindset bent on killing non-wolves around them, though, unlike the folklore and myths, it is found that they can be killed through normal damage without relying on silver or other special methods.
This incident only impacts the people within the continental United States, except for the state of Missouri. The rest of the world is not affected, but they have to deal with the questions of the event and how to handle those who turned. The short stories in Nation of the moon follow those affected and the challenges they must face as the next full moon approaches.