Tin Man (S01E18)

Col. Jack O'Neill and the SG-1 team arrive on PX3-989, only to be zapped by an electrical trap that renders them unconscious. When they awaken, they find themselves in an underground lab with Harlan, a strange but apparently peaceful native of PX3-989 who claims to be 11,000 years old — and who says he has not only fixed their injured bodies but improved them. When SG-1 returns to Earth, over Harlan's objections, the team members discover what he means. While they all feel like themselves, they are all now machines that have been implanted with the consciousness of the SG-1 team members. Worse, they will run out of power and die unless they return immediately to PX3-989. Upon their return, they confront Harlan, who, as a robot himself, is mystified by their demand that he put them back in their human bodies and sacrifice their immortality. Under pressure, he takes them to meet their human selves in hopes of brokering a compromise between men and machines. (Metro-Goldwyn-Mayer (MGM))