All good stories. Let me add one more (sort of recent) movie to the queue....
The Island(2005), PG-13, 136 min, Action, Adventure, Sci-Fi, 22 July 2005 (USA)
"It is described as a pastiche of "escape-from-dystopia" science fiction films of the 1960s and 1970s such as Fahrenheit 451, THX 1138, Parts: The Clonus Horror, and Logan's Run. The film's plot revolves around the struggle of Ewan McGregor's character to fit into the highly structured world he lives in, isolated in a compound, and the series of events that unfold when he questions how truthful that world really is. After he learns that the compound inhabitants are clones who are used for organ harvesting and surrogate motherhood for wealthy people in the outside world, he escapes."
“The Island” is actually a more moral world than the one of “Never Let Me Go”.
In “The Island”, the owners and workers don’t tell the clones their purpose and hide the fact that the agnates are conscious people from the world.
In “Never Let Me Go”, clones are created to be harvested, the world knows they exist, and they have some freedom of movement and interact with medical staff.
The horror of the ending is that Halvsham was a failure; people weren’t convinced clones had souls, so the harvesting of clones continued, and the conditions for the next generation of clones is likened to pig farms.
In short, the people of “Never Let Me Go” have dehumanized the clones such that they continue to kill them for parts and knowingly decided to do so. In “The Island”, the owners assume people would still be horrified to know they’d killed the clone if they knew it could think.