Shetland's Folk Festival has always been ambitious — bringing international artists to community halls, bars, and an audience that otherwise may not have been able to see them.
An inescapable part of the experience for visiting artists is to make the journey up from Aberdeen on the overnight, 14-hour ferry.
In 1988, a nationwide strike by the National Union of Seamen (NUS — now part of the RMT union) put the festival at risk.
Negotiations to allow the ferry to sail were conducted by an unusual source — the singer Elvis Costello.
He was a huge star, having made his name in the music scene's post-punk new wave.
Costello negotiated the passage of the ferry in exchange for performing a benefit concert for the workers on his return to Aberdeen.
The star was performing at the festival after a chance encounter with Shetland-born gig promoter Davie Gardner.
He was having an afternoon drink with friends in Lerwick's Thule Bar when in walked Elvis Costello.
It was a "jaw-dropping moment," recalls Davie.
"He was at the height of his fame and I was a huge fan."
After a few drinks, they got talking about the islands' music scene.
Costello asked about local festivals to which Davie recommended the Shetland Folk Festival.
"He said 'that sounds great' and connections were made from there."
The nationwide NUS strike began in January 1988. It was organised in solidarity with workers in the Isle of Man who had been sacked for not accepting new contract terms.
The union had negotiated a weekly ferry service that acted as a lifeline for the Shetland Islands. It would carry essential supplies for the islands, and staff would not take payment — rather the money would go to charity.
But some crew from the St Clair ferry joined the picket, meaning it would not make the Shetland sailing.
"Then, like now, a lot of equipment has to be brought in to do the festival," explained Davie Gardner.
The inability to transport equipment to Shetland was a disaster for the organisers.
The festival was at "huge risk," he said. "It nearly all went wrong."
A solution came in the form of Elvis Costello.
"He spoke to the union, he spoke to the dockers and promised to do a benefit gig on their way back from Shetland," said Davie.
Good to his word, he hired the Aberdeen Music Hall and performed a variety concert in May 1988.
In that month's copy of now defunct music magazine Melody Maker, Costello said "(the dock workers) were good enough to allow the boat to sail ... and I think it only respectful to do something for them."
As well as highlighting the strike and what the union was striking over, his impact on the folk festival that year was keenly felt.
"He probably single-handedly saved the Shetland Folk Festival that year, even before playing it," remembers Davie.
Costello was pleased to have performed the concert in Aberdeen.
In Melody Maker, he was reported as saying: "I agree with the NUS side of things.
"Anything we can do to get publicity for them ... must be good. I spoke to the pickets and they are just ordinary blokes trying to protect their jobs."
But perhaps the efforts of securing the passage to Shetland took their toll.
Speaking to BBC Radio Shetland in 2005 for the festival's 25th anniversary, Costello said he "didn't get off to a sparkling start."
He explained that on the overnight ferry he enjoyed "some silver birch wine — which is really lovely. But I did arrive (off the ferry) with a terrible headache."
Shetland, by way of the scenery and its music scene, left its mark on Costello.
In 2005 he said, "(Shetland) is a place ... that you're made to feel welcome."
Shetland has a special place in Costello discography. His Spike album is dedicated to all his "friends in the Thule Bar, Lerwick."
Likewise, audiences in Shetland and Aberdeen appreciated Costello.
Sue Beer has seen him perform three times, including Glastonbury, but maintained that the 100-person capacity Whiteness Hall in Shetland was the best of the concerts.
"The audience and Costello appreciated each other and fed off each other," she said.
She described the atmosphere as "electric" and that Costello, while not being an artist she might consider as being especially openly happy, had a face "full of joy because (the concert atmosphere) was working so well."
In Aberdeen, Mark Musk who was a student in 1988, said Costello held the sold out crowd in the Aberdeen Music Hall just by himself.
"Costello was saying how important it was to support (workers on strike)," he said.
Mark believes the singer himself could appreciate the effect he was having on the audience.
"Costello said 'this doesn't feel like a Wednesday afternoon. It feels like a Saturday night'."