The phrase comes from Doctor Who, spoken by David Tennant as the Tenth Doctor in the 2007 episode Blink, where he tries to explain how time travel works without using straightforward science. Its rhyming, tongue-twisting wording made it easy to quote, and fans soon lifted the short audio for edits, reaction videos and Doctor Who compilations online. It endures because it sums up the show's playful attitude to paradoxes in a few seconds, letting creators signal time travel, confusion or a clever twist without needing any longer explanation.