But bitter fans later learned they had been they had been victims of an elaborate hoax.
Rumours had been spreading like wildfire in Skåne that the world famous actor would be turning up at the festival.
Festival arrangers had promised “a special guest” in the weeks leading up to the show, and word had spread that Nicholson was in the area for a trip to visit his daughter, who lives in Copenhagen.
Those rumours reached fever pitch when reports suggested he was staying in a hotel in the town, and finally at around 10.30pm a car with blacked-out windows pulled and someone closely resembling the 74-year-old actor was led up to the stage.
Festival arrangers announced “We have a surprise for you”, as ‘Jack Nicholson’ strode into the spotlight.
With the audience still none the wiser he declared, “Here’s Johnny” the famous line from the classic horror movie “The Shining”, before uttering a quieter “I love you” and beating a hasty retreat.
It wasn’t until Sunday that it became clear the entire episode had been a hoax, using a lookalike who had been drafted in to replace the real Nicholson.
“We really didn’t mean to offend anyone,” Summer rock promoter Ulf Nilsson told The Local on Monday.
“The truth is that right up until the last moment we had been working hard to get hold of several big stars for the surprise guest slot.”
According to Nilsson, Swedish actor had Peter Stormare had been approached, as had “Elvis Presley’s best friend”.
“Then one European promoter who we had approached suggested we use a lookalike instead,” he said.
The news that the audience of 1,200 star-struck fans had been duped by the Nicholson imposter led to widespread disappointment and anger.
“I was standing 30 feet away and I was convinced it was him. But as it wasn’t, of course you feel very cheated,” 54-year-old Donald Holmes told the Expressen newspaper.
Festival promotor Nilsson however, remains unrepentant.
“I was surprised at the response because we didn’t set out to deceive people,” he said.
“I just think that people are annoyed with themselves for falling for it more than anything else, and now they just want a scapegoat.”
Ticket agency Ticnet, which for a short while had also announced the appearance of Nicholson, claims that it was the responsibility of the promoter to say who would and would not be appearing.
In addition, several local media outlets which were also duped by the hoax have been forced to hastily re-write stories about the event when the truth came out.