The family must decide to kill one of them in order to save all of humanity

Eric, Andrew, and their daughter Wen are on vacation at a peaceful cabin. Wen is out collecting grasshoppers when Leonard approaches her and says he wants to be her friend. Soon after, Sabrina, Adriane, and Redmond all make their way over while holding unusual-looking weapons. Wen and her father secure the cabin, but Leonard and the others quickly break down the door and enter. Leonard makes a startling demand after he has restrained Eric and Andrew: The family must choose to murder one of them in order to preserve all of mankind. If not, the end of the world is near.