Nike's "Just Do It" slogan has a truly creepy back story.

It all started with a murderer…

Nike is now one of the most coveted and well respected shoe makers on the market. But there used to be some pretty fierce competition between Nike and Reebok for the top spot.

In 1987, Nike needed to come up with their best campaign ever to surpass Reebok’s $1.4 billion dollar revenue. They needed something catchy. Something unique.

That’s where the murderer part comes in.

Dan Wieden of Wieden + Kennedy PR was the man in charge of creating Nike’s advertising campaign. The thing is, he couldn’t think of a catchphrase.

“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.”

With the deadline looming, Dan started to think… well, outside the box.

“For some damn reason I thought of Gary Gilmore…”

Who, you ask, is Gary Gilmore?

Gary Gilmore murdered two men in Utah and was sentenced to death in 1976. His case received a whirlwind of media coverage because capital punishment had been prohibited from 1972-1976.

He also gained notoriety because his famous last words, as he sat before the firing squad, were “Let’s do it!”

Interesting choice.

Dan the advertising man remembered Gary’s case, of all things.

“I remember when I read that I was like, ‘That’s amazing — how, in the face of that much uncertainty, do you push through that?’

“I didn’t like the ‘let’s’ thing, I just changed that because otherwise I would have to give him credit. Now I don’t really have to.”

And Nike loved it.

The “Just Do It” tagline first appeared in a 1988 commercial featuring 80-year-old runner Walt Stack and was wildly successful.

It allowed Nike to regain the lead from Reebok in 1990 and grow its worldwide sales from $877 million to $9.2 billion in the decade after it was launched.

Click through our gallery of Nike women being #fit

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