Other mistake: One visual that has always bothered me that I could not find in your list were the scenes when the mother ship first appears. It's enormous scale appears to dwarf Devil's Tower and the whole surrounding area actually, but when it moves over to the "landing strip" area and begins to rotate 180° (right-side up?), it suddenly seems to shrink to a much smaller size and mass during the slow revolution. On its originally-seen scale above/behind the tower, one would think that either the great ship's outer prongs would have been torn off, or more likely the impromptu landing site and most of Devil's Tower would have been destroyed as the huge craft rotated itself. The visual scales just do not stay consistent throughout the film's climactic final act.
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Close Encounters of the Third Kind (1977)
Plot summary
Directed by: Steven Spielberg
Starring: Lance Henriksen, Richard Dreyfuss, Teri Garr
Cableman Roy Neary (Richard Dreyfuss) is one of several people who experience a close encounter of the first kind, witnessing UFOs flying through the night sky. He is subsequently haunted by a mountainlike image in his head and becomes obsessed with discovering what it represents, putting severe strain on his marriage. Meanwhile, government agents around the world have a close encounter of the second kind, discovering physical evidence of otherworldly visitors in the form of military vehicles that went missing decades ago suddenly appearing in the middle of nowhere. Roy and the agents both follow the clues they have been given to reach a site where they will have a close encounter of the third kind: contact.
David Laughlin: We didn't choose this place! We didn't choose these people! They were invited!
Claude Lacombe: They belong here more than we.
Trivia: After this movie, young Cary Guffey got to play the part of an alien himself - in the Italian movies "Uno Sceriffo extraterrestre - poco extra e molto terrestre" (English title: "The Sheriff and the Satellite Kid", 1979) and its sequel "Chissà perché. capitano tutte a me" ("Everything Happens To Me", 1980); both with the Italian actor Bud Spencer.
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Answer: It wasn't definitively answered, but it appears the aliens took people in order to learn more about humans. It's unclear if all those who were returned had originally gone willingly, but the intent was not to keep them indefinitely or harm them, and they were returned to Earth, albeit many decades later. At the end, after the aliens had made contact, a new group of humans, including Roy, went with them voluntarily.
raywest ★