The line comes from the TV series Dexter and is associated with Sergeant James Doakes, played by Erik King. Short clips of the quote spread widely through meme compilations, Vine-era edits and reaction videos because the delivery is so abrupt and easy to match with a surprise entrance. It remains popular in short-form content as a reveal cue, much like the bruh meme or It was at this moment he knew when creators want a fast, recognizable reaction sound.