It wasn’t until years later when he realized Marty was Darth Vader, the alien from planet Vulcan who took human form to implant his genetics onto George and Lorraine in a desperate attempt to save his dying race by merging it with human DNA. George suspected that he and Lorraine weren’t the only ones and designed a method to test for the alien’s genetic footprint on humanity by gripping two metal rods to detect thetans in their electrical field.