The sinister story of Nike's 'Just Do It' slogan, which was inspired by the last words of a murderer before he was executed

• Nike's iconic "Just Do It" slogan was inspired by the final words of a notorious killer in 1970s Utah.
• Facing down a firing squad in his last moments, double-murderer Gary Gilmore said: "Let's do it."
• Dan Wieden, the founder of ad agency Wieden and Kennedy, was inspired to adapt the phrase to "Just Do It" for a 1988 TV ad which introduced the slogan to the world.
• Looking back in 2009 he said: "None of us really paid that much attention. We thought 'Yeah. That'd work.'"
• Visit INSIDER's homepage for more stories.

It may seem hard to believe, but one of the best-known marketing slogans of all time - Nike's "Just Do It" - was inspired by the last words of a murderer.

"Just Do It" was dreamed up by Dan Wieden, the head of ad-agency Wieden & Kennedy, who included it as the focal point of a TV commercial in 1988.

A little-known fact about the endlessly-repeated tagline is that it was inspired by the final words on death row of a double-murderer: Gary Gilmore, who killed two people in Utah in 1976.

Gilmore robbed and killed a gas station attendant, and then a motel worker, according to US Supreme Court records.

The record shows that Gilmore shot himself in the hand in the process, and fled to his cousin Brenda's for medical aid, but she turned him over to police.

Gilmore was sentenced to death in October, and sent to Utah State Prison the same year. When he reached the end of death row three months later, on January 17, 1977, he was asked if he had any last words.

Facing down a five-man firing squad, Gilmore said: "Let's do it."

"I like the "do it" part of it," Wieden told filmmaker Doug Pray in his 2009 documentary "Art & Copy".

"None of us really paid that much attention," he recalled of the team working on the Nike ad. "We thought 'Yeah. That'd work.'"

In a separate interview with design website Deezen, Wieden said: "I was trying to write something that would tie it up, so it could speak to women who had just started walking to get in shape, to people who were world-class athletes - and it had the same kind of connection with them."

Nike debuted the slogan in a 1988 commercial about an 80-year-old runner named Walt Stack. The brand's sales subsequently exploded.

In "Art & Copy," Nike's former marketing chief Liz Dolan said that Nike tries not to share the origins of the phrase widely.

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"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."

Davide Grasso, vice president of global brand marketing at Nike, told Creative Review in 2011: "'Just Do It' is still as relevant to us as a brand today as it was 23 years ago."

"It has been translated into many, many languages."

"One of my favourite examples is this one: The American Foundation for the Blind gave Nike the 1995 Access Award for its creation and distribution of a "Just Do It" poster done in braille."

INSIDER contacted Nike for comment on the history of "Just Do It," but has yet to receive a response.