The clip comes from The Power of the Daleks, a 1966 Doctor Who serial built around the Daleks, the armoured alien villains known for their grating voices and cry of extermination. In the story the Daleks chant conquer and destroy as they assert control, a moment that captures their cold, collective menace. Shared later as a short soundboard clip, it spread among Doctor Who fans and meme editors who recognised the chant instantly. It remains popular because the line needs no context to signal an unstoppable, over-the-top takeover.