xkcd #3232: Countdown Standard
Title text:
Anyone who is caught counting 'three ... two ... one ... zero ... GO!' will be punished with a lifetime of eating only ISO standard food samples.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3232/
Name this movie:
John Lithgow: “okay this is just a practice, nobody do ANYTHING. 3 - 2 - 1 - cut.”