Soylent Green is a 1973 American ecological dystopian thriller film directed by Richard Fleischer and starring Charlton Heston, Leigh Taylor-Young, and Edward G. Robinson (in his final film appearance as well as his posthumous work due to his death in January 1973). Loosely based on the 1966 science fiction novel Make Room! Make Room! by Harry Harrison, it combines both police procedural and science fiction genres: the investigation into the murder of a wealthy businessman; and a dystopian future of dying oceans and year-round humidity due to the greenhouse effect, resulting in suffering from pollution, poverty, overpopulation, euthanasia and depleted resources.