On 7 May 1964, a gaggle of excited passengers alighted on to a rainy disused railway station platform in south Manchester and took their seats for what one of the city's leading music academics says was a "massively culturally significant" gig.
The show at Whalley Range's Wilbraham Road station, recorded for Granada TV as the Blues and Gospel Train, saw greats including Muddy Waters and Sister Rosetta Tharpe perform.
The University of Salford's Dr Chris Lee says the show "influenced nearly everyone who saw it" and was as important as the Sex Pistols' 1976 show at the city's Lesser Free Trade Hall, which spurred attendees Morrissey, Mark E Smith and the musicians who would become Joy Division and Buzzcocks into action.
The gig was born out of the Blues and Gospel Tour, which was touring Europe for a second year running, having made its debut in 1963.
The line-up was the stuff of musical legend - alongside Waters and Tharpe were Sonny Terry and Brownie McGhee, Cousin Joe, Otis Spann and the Reverend Gary Davis.
But while in 1964, the tour was a hit across the country, Dr Lee says the previous year the only British stop was in Manchester.
'Country catching up'
That, he says, is exactly why the TV programme came to be made in the city.
"Manchester was the hottest blues and jazz scene in the country and we already had a very big R'n'B appreciation scene.
"The Twisted Wheel [nightclub] had been operating since 1961, playing more or less all urban black music and concerts at the Free Trade Hall were always sold out.
"In fact, Manchester was the only place that took the first tour in 1963 - what many people don't know is that a minibus came from London to that show and in it were Eric Clapton, Jeff Beck, Keith Richards and Brian Jones. They came all that way just to watch the concert.
"So by 1964, the country was catching up with Manchester.
"Johnnie Hamp, the legendary Granada TV producer, had booked them the year before and did so again, only this time instead of it being in a studio, he had the great idea of staging it in a disused train station in south Manchester."
Mr Hamp himself says the idea for the station set rolled out of an early show he had done, in which he hired three trains as a backdrop for Little Eva's The Loco-motion.
"Hiring them meant I had a relationship with the railways, so when we decided to do the second blues show outside of a studio, they tipped me off to the derelict station.
"I asked if they could throw in a train as well, which we dressed with a cow-catcher and such like, and everything fell into place.
"Of course, the imagery of the trains, the whistle blowing in the distance, is one that is long associated with the blues."
The station was dressed up to look like one from the American South, but typically for Manchester, the weather did not echo that area's dustbowl conditions.
Shortly after the train which carried the audience the few miles south from Manchester's city centre pulled in, a storm lashed the station.
Mr Hamp says the downpour would have been his worst memory of the show had it not led to his best.
"Sister Rosetta came to me and asked if she could change her opening number to Didn't It Rain?," he said.
"When she strapped on her guitar, it was astounding."
Dr Lee says the "brilliant sequence where she and Cousin Joe cakewalk along the rain-soaked station" after her arrival in a carriage and her stunning version of the song was also one of his highlights.
Audience member John Miller, who was in his 20s at the time, picks Sister Rosetta's performance as his "outstanding memory" of the night too.
Unlike many at the show, he was not on the train from Manchester, but lived locally and went along simply "because I was a blues fan".
"My brother-in-law called to say that if we got down to the station, there was a chance of a free concert.
"We just walked in and sat down, as did several others - and it was a really good time."
'Reignite their popularity'
Dr Lee was not at the station, but was one of "something like 10 million viewers" who tuned in at home.
He says it was the TV broadcast that gave the show its significance, as "it turned a lot of people on to the music".
For him, "the same thing could be argued for this broadcast" as for the aforementioned Sex Pistols' show.
"Young people saw it and thought 'right, I need to form a blues band'."
The list of musicians who have told Johnnie Hamp that the show influenced them is staggering.
"Mick Jagger, Jimmy Page, John Paul Jones... the list goes on. You have to remember that Muddy Waters, Sonny Boy, Sister Rosetta - they were icons to us."
Dr Lee says the TV show was also important because "the images that we were getting from America on TV at the time were the civil rights marches, where people were being attacked with hoses and clubs".
"This show allowed us to see living witnesses to that struggle."
He says that the differences were not lost on the artists themselves either, as they "were amused that they didn't have to sit in different restaurants and travel in different coaches on the trains over here".
Mr Hamp says there was another reason for the performers to be keen to play Europe.
"In America, their major popularity had passed, as the young audience moved on to Motown and the like.
"Europe was a chance to reignite their popularity on the other side of the Atlantic."
'Bizarre but great'
As for the setting, on a platform mocked up as "Chorltonville", Dr Lee says it was "bizarre but it was great and visually, it was like nothing that had come before".
"Nobody had tried anything like that - and the performers loved it.
"Sister Rosetta couldn't believe she was brought to the stage in a horse-drawn carriage - she was used to limousines."
Dr Lee says he watched the show with his mother because they were fans of the blues.
And like Mr Miller, it was Sister Rosetta Tharpe's Didn't It Rain that stood out for them.
"She straps on an electric guitar and blows everybody away.
"Lots of people, myself included, were looking around for the bloke playing lead guitar - and it's not [anyone else], it's her.
"It was absolutely mind-blowing - a great song and a great gospel singer belting it out."
FOR MORE ABOUT SISTER ROSETTA, CLICK HERE