Overpopulation has overstressed the food-production capacity of the planet, resulting in desperation at all levels. Detective Thorn (Charlton Heston) shares an extremely tiny "apartment" with retired researcher Soi Roth. In the overpopulation depicted here, it is impossible to get anywhere without walking over, under, or around someone. Thorn has been hired to investigate the murder of a top industrialist, the man whose company manufactures the life-sustaining wafers called Soylent Green, the only means of survival for the swarming hordes of poor people.