The line comes from National Lampoon's Christmas Vacation, released in 1989 and starring Chevy Chase as Clark Griswold. It appears in his late film rant after a string of disasters ruins his plans for a perfect family holiday, turning an earnest Christmas wish into a sarcastic outburst. Clips of the speech circulate every December on social media and soundboards, where the shortened hap hap happiest Christmas excerpt is reused as a reaction to stressful, chaotic, or disappointing festive moments.