"Soylent Green is..." no longer much of a surprise since Charlton Heston's climactic line has joined Planet of the Apes' "You maniacs" rant in the oft-quoted annals of Heston overacting. One of a cycle of early-'70s downbeat eco-science fiction films akin to Silent Running (1971) and Heston's The Omega Man (1971), Soylent Green presents Heston as another dystopian savior in a future shock vision that teeters on the fine line between clever and stupid. When not sleeping with dead magnate Joseph Cotten's comely "furniture" Leigh Taylor-Young (apparently feminism went down the drain with the food supply), Heston attempts to solve the mystery of Cotten's murder. The sickly green exterior haze, people sleeping on stairs, and the bulldozers that disturbingly clear riots, however, are enough to tip us off to the insidious secret ingredient in everyone's favorite bio-engineered snack long before Chuck witnesses the "waste" processing plant himself. Still, the opening montage of 20th century decay and Edward G. Robinson's heartfelt performance (in his final film) as a man old enough to know how beautiful and well-fed the earth used to be give moments of emotional heft to Soylent Green's ominous -- and still timely -- message about environmental desecration.