About
Oh My God, You/They Killed Kenny! (sometimes accompanied by You Bastard!) is a recurring phrase in the animated television show South Park, in which the character Kenny McCormick is regularly killed off though the first 5 seasons only to return completely fine later on.
Origin
South Park was first released in 1997, and though 2002 Kenny was killed off in various ways for the sake of a running gag.
Spread
It is commonly repeated by fans and and other fans of the show.