Angry Michael Jackson fans are seeking refunds on their tickets for the World Music Awards.
Entry to the award show cost as much as £100, and fans say they were misled by promises that Jackson would perform a version of his hit single, Thriller.
"I'm furious," said Katherine Kidd, who spent £200 to get to the show. "I feel like I've been ripped off."
Jackson only sang a few lines of We Are The World before leaving the stage. Thriller was performed by Chris Brown.
"It was a huge anti-climax," said 29-year-old Londoner Zareen Iqbal. "I just walked off."
"People were expecting something significant but he didn't perform at all," said Abdo Binmadhi, who travelled from Oxford for the show at Earls Court in London.
"When the lights went on I saw people's faces and they were like: 'Is that it?'"
"I should have just stayed at home and watched it on TV... We should definitely get a refund."
The organisers of the World Music Awards said that they had "not been contacted by any of the fans or had one complaint" regarding the event.
They added that Jackson's performance had been cut short because the ceremony over-ran, breaking a noise curfew at the venue.
"I was standing watching Jackson perform... and suddenly he stopped," said Julius Just, head of Public Relations for the awards.
"They cut the sound on one of the greatest living artists in the world.
"It's the first time anything like this has happened in 18 years of the World Music Awards."
But officials at Earl's Court denied that the sound had been cut.
"We accommodated the show and the show's organisers by obtaining an extension to our licence in order to allow the show to run to eleven o'clock," said spokesman Jeremy Probert.
"And as far as we're concerned, that's what the show did. As a matter of fact, I think it finished about a minute-and-a-half early," he added.
However, not everyone at the award ceremony was left disappointed by Jackson's performance.
"I thought it was fantastic," said Joseph Dougal, from East Kilbride, in an email to the BBC.
"None of the fans expected him to give a performance, so it was a true surprise."
Adam Saunders, 26, bought tickets for his fiancée, Caroline, who had waited all her life to see Michael Jackson.
"It was worth it just to see her happiness at seeing him on stage," he said.
"She just kind of went numb. There were tears in her eyes."
Paolo Mariani, who was part of the 50-strong choir that sang with Jackson, called the performance the "best experience of my life".
The 17-year-old, who has never sung professionally before, was hand-picked for the chorus last week, shortly after the pop star confirmed his appearance.
"It was so rushed that we didn't even have time to rehearse with Michael Jackson," he said.
"We got there at one o'clock on the day of the show and basically rehearsed in a room with a choreographer for a couple of hours.
"We were rehearsing to sing the whole song - so we were a bit confused because we never got to the actual song. The music was just cut off.
"I can see that fans might have felt let down, but for us it was amazing."