The line comes from the 1939 film The Wizard of Oz, where Dorothy and her companions chant it nervously while entering the dark forest on their way to see the Wizard. Spoken as a group, it became one of the film's most quoted moments and a shorthand for facing something frightening. Decades later, the phrase spread through television parodies, Halloween specials, and online reaction clips, where the familiar rhythm makes it instantly recognisable even without the film. Its staying power comes from that mix of nostalgia and simple, escalating fear.