Here is another beautiful work by one of my favorite animation artists, RENE LALOUX, called Gandahar, known in the English version as Light Years. According to the plot, the utopian world of Gandahar is threatened by destruction as foretold by a mysterious prophecy. Queen Ambisextra and the Council of Women send the warrior Sylvain to discover the meaning of the riddle and to save their paradisiacal homeland. He discovers an army of preprogrammed metallic humanoids who form a militant slave society that threatens to destroy Gandahar. The metal soldiers kidnap Gandaharians by emitting paralyzing rays that send the bodies of those they capture through a portal. Later these captives return as a slave member of their society, also encased in metal. You can watch the whole movie in parts on youtube to find out what happens.
The original version was directed by René Laloux, and was based on Jean-Pierre Andrevon's novel Les Hommes-machines contre Gandahar (The Machine-Men versus Gandahar). An English version was produced by Harvey Weinstein, and noted science-fiction author Isaac Asimov made the revision of the translation.