Point of View (S03E06)

Stargate Command is taken aback when an alternate-reality version of Samantha Carter and the deceased Maj. Kawalsky are found in a secured building in top-secret Area 51. To transport themselves to our present-day Earth, they used the Quantum Mirror ("There But for the Grace of God"). When the alternate Dr. Carter and Maj. Kawalsky are taken to SGC for debriefing, they can't believe how different everything is in this reality. Here Col. Jack O'Neill is alive and single, whereas in their alternate reality he was married to civilian scientist Dr. Carter before his recent death at the hands of the Goa'uld. They're also stunned that Teal'c is an ally rather than an enemy, this world's Maj. Kawalsky has been dead for several months, and this Samantha Carter is a major who would be identical to her civilian alternate if not for her short hair. Dr. Carter begins to suffer from temporal distortion, a side effect caused by travel through the quantum mirror. Maj. Carter determines that Dr. Carter and Maj. Kawalsky will die unless they are returned to their original reality. Unfortunately, in their reality, the Goa'uld are swarming through Stargate Command and returning home means certain death. SG-1 must use their present-day resources and knowledge to return with their new acquaintances and overthrow the Goa'uld. (Metro-Goldwyn-Mayer (MGM))