 In a running gag most prevalent during the first five seasons of the series , Kenny would suffer an excruciating death before returning alive and well in the next episode with little or no definitive explanation given . Stan would frequently use the catchphrase " Oh my God ! They killed Kenny ! " Followed by Kyle exclaiming " ... You bastards ! " . Media commentators have published their interpretations of the many aspects of the running gag from philosophical and societal viewpoints . Since the show began its sixth season in 2002 , the practice of killing Kenny has been seldom used by the show 's creators . Various episodes have set up the gag , sometimes presenting a number of explanations for Kenny 's unacknowledged reappearances . 
