Sole survivors of a man-made catastrophe that has destroyed earth’s atmosphere, Billy (Mark Duplass) and Ray (Sterling K. Brown) are childhood friends who have managed to embrace the new normal from within their domed biosphere, an artificial ecosystem which Ray - a brilliant scientist - designed to provide them with the necessary life support.

When the last female fish in their pond perishes, leaving behind only two male specimens, extinction seems like a given unless life beats the odds and adapts.