A young girl named Wen (Kristin Cui) and her two fathers (Jonathan Groff, Ben Aldridge) go on vacation to a remote cabin in a forest. They have fun swimming in the lake, and while her fathers are relaxing on the deck, Wen collects and and classifies insects. Suddenly, she notices a strange man walking through the woods towards the cabin.
The man, named Leonard (Dave Bautista), introduces himself to Wen. He's soon joined by three others (Rupert Grint, Nikki Amuka-Bird, Abby Quinn). Wen and her fathers barricade themselves inside the house, but the four armed strangers break in. Leonard tells them they're there to prevent the apocalypse and to do that, they have to ask the family to make a terrible decision. With limited access to the outside world, the family must decide what they believe before all is lost.