The Magazine's review of advertising
THE ADVERT: Madonna, singing Like a Prayer for Pepsi in 1989
THE SCHTICK: The cola wars in full swing, Pepsi wheeled out its big gun - the Queen of Pop - to perform her latest single
Madonna's "young self" in the advert
THE BREAKDOWN: It was, the TV voiceover promised us, not to be missed. The Material Girl was to put the fizz into Pepsi's campaign - for a fee of $5m.
The premiere of Madonna's Like A Prayer in a two-minute advert was notable enough to be reported on ITN's News At Ten, and ITV ran trailers advertising when it would be shown - 8.12pm on Thursday 2 March, 1989.
But within 48 hours of the much-hyped worldwide premiere, the company pulled the ad, and it was never screened again.
This was because influential church groups in the United States had threatened a mass boycott of Pepsi products, troubled by the Catholic-born star's ongoing flirtation with religious imagery.
The ad starts with Madonna watching black-and-white footage supposedly of her own eighth birthday party.
While our commercial bore no resemblance to the video, many people who were offended by the video made no distinction between the two
Then magically, the star and her younger self switch places. Mini-Madonna wanders around the singer's apartment, marvelling at posters of her adult self and finds the same doll she has been given as a birthday gift. The ad ends with grown-up Madonna telling her young self "go ahead, make a wish" - as they both drink Pepsi.
That slogan was intended to become as synonymous with Pepsi as "It's the real thing" is with rivals Coke. But the feelgood factor did not last long for its executives.
Within a couple of days came the second act in the drama. The video for Like A Prayer hit TV screens.
It was great for anyone religious - it shows Madonna witnessing an attack and then going to a church for guidance
Leon, who played the black saint
It opened with Madonna fleeing the scene of a rape. She runs into a church and prays before a statue of a saint, played by a black actor, before flashbacks reveal she witnessed the attack, carried out by a white man. But an innocent black man (the saint's double) is arrested.
There are burning crosses and Madonna suffers stigmata before heading off to put right this miscarriage of justice.
Within hours, American religious groups complained about the portrayal of Jesus Christ (as some viewers assumed the saintly character to be) as a black man being kissed by Madonna.
With MTV unlikely to ban the video, the groups tried a new tack - threaten to boycott Pepsi.
The campaign was promptly shelved. Twenty years on, a Pepsi spokesman says it was an unfortunate episode.
"While our commercial bore no resemblance to the video, many people who were offended by the video made no distinction between the two. We felt that the only appropriate step under the circumstances was to immediately stop airing the commercial."
Ruth Mortimer, associate editor of Marketing Week, says that today there would be even more of a reaction.
"Religious groups know what they can achieve if they complain. Big companies in the States tend to be particularly sensitive in that area."
When it comes to celebrity advertising campaigns, companies buy into the star's image.
And when things go wrong for that person, it's time for a corporate rethink. Wrigley's chewing gum recently withdrew its adverts starring singer Chris Brown, who is facing assault charges.
Ms Mortimer believes Pepsi had little choice: "You have to weigh it up carefully, whether the complainants come from a group that are particularly likely to buy your brand.
"Pepsi is a very mainstream brand so it's quite difficult for them to do something edgy."
LIKE A PRAYER
Title track from Madonna's fourth album
Single spent three weeks at number one in UK and US
Her eighth best-selling UK single
It won an MTV award and Madonna thanked Pepsi "for causing so much controversy"
Since 1989, Pepsi has had more big-name celebrity endorsements (Britney, Beyonce and Beckham) while Madonna has fronted campaigns for companies as varied as Max Factor, BMW, Versace and Gap.
Clare Parmenter, of the Madonnalicious fansite, says Pepsi should have realised Madonna might be a controversial choice.
"She has become more famous for shocking people since then. It seemed like it was the start of her really pushing the boundaries."
Leon remained friends with Madonna and once took her to a reggae club
So what happened to the other central figure in the drama - the black actor who played the saint and the innocent man?
Leon (who, like Madonna, eschews his surname) went on to star in Cool Runnings, Disney's 1993 film about Jamaica's bobsleigh team.
He's also appeared in Sylvester Stallone's Cliffhanger and Ali with Will Smith, and in TV films about The Temptations, Jackie Wilson and Little Richard.
He recalls: "I didn't want to do a pop video. I saw myself as a serious actor and all I knew of Madonna was her dancing around. But I was persuaded to meet the director and hear the concept."
He did not see the storyline as controversial. "I actually thought it was great for anyone who is religious. It shows Madonna witnessing an attack and then going to a church for guidance.
"I really think that Pepsi made a hasty decision, but it was their own money they were throwing away."
Ad Breakdown is written by John Hand