Nike’s ‘Just do it’ slogan is undoubtedly a killer line – and now it’s been revealed that the inspiration for it came from an actual killer.

The phrase, first used in a Nike advert in 1988, was pitched to the firm by advertising executive Dan Wieden, who admitted that it was borrowed from something a Utah murderer uttered as he faced a firing squad.

The condemned man in question was Gary Gilmore, who was sentenced to death in 1977 for robbing and murdering two men in Utah the previous year.

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Nike’s ‘Just do it’ slogan is undoubtedly a killer line – and now it’s been revealed that the inspiration for it came from an actual killer

The tagline 'Just do it', which has become synonymous with the Nike brand, first appeared in 1988 at the end of an advert featuring 80-year-old runner Walt Stack (pictured)

Gary Gilmore (pictured) uttered the words 'let's do it' before he was executing by firing squad for two Utah murders in 1977. The phrase inspired one of the most successful advertising slogans of all time

He chose to be executed by firing squad and it was reported that he said ‘let’s do it’ in the moments before he died.

Mr Wieden, speaking at an advertising conference in Cape Town in February, said that he recalled this line in 1988 just before he had a crunch marketing campaign meeting with Nike bosses, and decided to suggest a slightly altered version as a slogan.

This week Mr Wieden, co-founder of advertising agency Wieden+Kennedy, repeated the story to Dezeen magazine.

He described how he was worried that an upcoming series of five TV adverts lacked cohesion, because they all had a different feel to them. He felt they needed a tagline to tie them all together.

His company had been parachuted in by Nike to help them counter-attack rivals Reebok, who had just announced bigger profits.

Dan Wieden (pictured) revealed that the slogan 'Just do it' was borrowed from the last words of Utah murderer Gary Gilmore

Mr Wieden said: ‘We… came up with five different 30 second spots. The night before [a meeting with Nike] I got concerned because… there wasn't an overlying sensibility to them all. Some were funny, some were solemn. So I thought… we need a tagline to pull this stuff together.

‘I wrote about four or five ideas. I narrowed it down to the last one, which was "Just do it". The reason I did that one was funny because I was recalling a man in Portland.

‘He murdered a man and a woman, and was put before a firing squad. And they asked him if he had any final thoughts and he said: "Let's do it." And for some reason I went: "Now damn. How do you ask for an ultimate challenge that you are probably going to lose, but you call it in?" So I thought, well, I didn't like "Let’s do it" so I just changed it to "Just do it".’

At first, he recalled, Nike hated the idea, but he won them round and the slogan appeared at the end of an advert featuring 80-year-old runner Walt Stack.