“Just Do It” has been the slogan of Nike since 1988. The words evoke visions of bold determination and inspirational challenges to be your best. Far from inspirational, the origin of the slogan tells a much darker, somber story.

Gary Gilmore robbed and killed a Utah gas station attendant and a motel worker in 1976. After being turned in by his cousin, Gilmore was arrested, convicted, and sentenced to death for two counts of homicide. He spent three months on death row before coming up before the firing squad on January 17, 1977. When asked if he had any last words, Gilmore directed his attention to the five-man firing squad and said, “Let’s do it.”

Eleven years later, advertising agent Dan Wieden was charged with coming up with a marketing strategy for Nike. He remembered Gilmore’s defiant last words and wondered if he could make use of them in his project.

With a subtle change of one word, a convicted murderer’s final words, “Let’s do it” became an internationally-known trademark of “Just Do It.”

Nike’s former marketing chief Liz Dolan said that Nike tries not to share the origins of the phrase widely. “That was not the version I heard when I arrived at Nike,” she said of Wieden’s inspiration. “I’m sure they didn’t want anyone to really know.”

Nike debuted the slogan in a 1988 commercial about an 80-year-old runner named Walt Stack. It has been the central marketing element of the company’s advertising strategy ever since.

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