Roth takes Soylent's oceanographic reports to a like-minded group of researchers known as the Exchange, who agree that the oceans no longer produce the plankton from which Soylent Green is reputedly made, and infer that it must be made from human remains, as this is the only conceivable supply of protein that matches the known production. Unable to live with this discovery, Roth seeks assisted suicide at a government clinic called "Home."
Thorn rushes to stop him, but arrives too late, and is mesmerized by the euthanasia process's visual and musical montage – a display of forests, wild animals, rivers, and ocean life, now extinct. Under the influence of a lethal drug, Roth tells Thorn his discovery and begs him to expose the truth. To this end, Thorn stows himself aboard a garbage truck to the disposal center, where he sees human corpses converted into Soylent Green. Returning to make his report, he is ambushed by Fielding and others.