An apocalyptic world, underground in a shelter. Allen, a man with a free will measuring machine, is determined to find someone who can score over 8%, conflicting with his sister's pressure to come out and help the community. By chance, she's brought a mentally challenged patient with her this time. Allen understands only the insane can display true free will, and when people from the outside are about to break into his place, he has to go down the rabbit hole in order to find existence. Maybe being free simply means being crazy.