A version of this article was first published on 11 November 2017.
Rewind to July in Istanbul, and a little-known team from Sweden stand on the brink of history as the clock ticks down on the second leg of their Europa League qualifier against Turkish giants Galatasaray.
With five minutes remaining, Ostersunds FK chairman Daniel Kindberg rises from his seat and makes his way down the steps of the Turk Telecom Arena, ready to join his players in celebrating a 3-1 aggregate victory - the biggest result in the club's history.
Kindberg knows the players will have to handle the final whistle right, just as they have the 180 minutes of football that preceded it.
The Gala fans are known for their ferocity and have already shown their displeasure at the impending defeat by a supposedly vastly inferior Swedish opponent.
When the referee blows, there are predictable whistles and boos and insults directed at the home side.
And then comes the applause...
"I was stunned," Kindberg tells BBC Sport. "The Turkish supporters - who had been very hostile at the beginning - rose up and applauded us off the pitch.
"I asked some of the staff, 'What is this?' And they were shocked. Galatasaray were founded in 1905 and they said that never in their history had they applauded a team off. It had never happened before.
"Our players were fantastic. They were lions, they were brave. These are the proud moments that give us the energy we need to continue when people tell us it is impossible. It is not."
Impossible. Back in 2010, it was a word Kindberg heard a lot when he discussed his plans to turn a side from a subarctic city that had just been relegated to the Swedish fourth tier with average gates of 500 into one of Europe's elite. He doesn't hear it so much these days.
Back then, the idea of taking on Arsenal in the last 32 of the Europa League was an impossible dream. On Thursday, it will be a reality.
To fully understand Ostersund FK's remarkable rise we must go back to the beginning, to eight years ago, when the club hit rock bottom...
Daniel Kindberg: As you know in 2010 we struggled badly and we were relegated, which wasn't good. I said I couldn't be involved in this and I left. To make a long story short, the players said: "If you don't come back, we quit." So I did something I don't do, I took a decision on emotion and I came back.
We sat down and talked - six, seven people - put out the emotions and asked ourselves why. Why do we do this? Why are we in the club? We work for free, why do we put in all this effort? What do we want to see? What do we want with our ambitions in football? What is everything about?
Through that process, we created our values and ambition of where we should be - to be in the elite part of football and play European competitive football in our stadium. People thought we were lunatics. Maybe they were right.
I called a friend of mine [Graeme Jones, assistant to Roberto Martinez at Swansea, Wigan, Everton and now Belgium] and I was upset. I said to him: "Why can I never find a good manager? They are all lousy. What should I do?"
He said to me: "Daniel, the problem is you, you keep picking the wrong ones." So I asked him to give me some proposals.
He called me back in a couple of weeks and said: "I've spoken to people, I know exactly who you should talk to - he is the one, the perfect match." I went over to meet him and, even if I don't want to admit it, Graeme and Roberto were right.
The man in question was Englishman Graham Potter. A former full-back, he had Birmingham, Stoke, Southampton and West Brom on his playing CV and coaching ideas in his head - but until then nobody willing to offer him the opportunity to put them into practice...
Graham Potter: I took the decision to stop playing at 30 because I knew the game was going to kick me out at some point. The phone calls from Barcelona and Manchester United weren't exactly coming my way.
I did the traditional coaching badges, but didn't feel it was the right way to go - so I did a teaching qualification and ended up with a job at the University of Hull. That started a five-year period there, making mistakes, developing, learning and working with the people at the university and coaching the students.
I thought I needed to test myself in the real world but I couldn't get any opportunities in England. I'd been out of the game. Then Ostersund came up through a contact [Jones], who put me in touch with the chairman. He had an idea and a philosophy at the club to do something different.
Potter agreed to become Ostersunds FK coach in December 2010 and moved to Sweden with his family in January 2011...
GP: My wife had built up a business for 10 years and we'd just had our first child. So in that way it was a big move, it was her leaving her life. It's not as if we were coming to Monte Carlo or a big football place - it was the fourth tier of Swedish football. It was a gamble.
It was January/February. It's -25C outside so there's not so much you can do, getting to know people. Ostersund had just been relegated so it wasn't in a positive place. People didn't believe in the club and didn't really like the club, if I'm honest.
My wife went to the local nursery and she was asked: "What are you doing here?" "My husband's got a job." "Great, what is it?" "Football coach." 'Who for?" "Ostersund." "I'd go home if I were you."
Success came quickly. They would win back-to-back promotions in Potter's first two seasons at the club - lifting them to the second tier of Swedish football - and the new ethos of the club was cemented...
GP: For the first couple of years it was impossible to get people here from the south of Sweden because there was no history, no tradition, no culture. They're not going to come for the snow, as agents used to say. So we had to provide an identity, a football style that was maybe interesting to people and didn't fit into the traditional Swedish culture.
We wanted players who had their careers ahead of them or would bring a bit of personality to the club. Jamie Hopcutt was someone we brought in in the second year. I knew him from York City, he was a talented player who wasn't ready to play first-team football in England physically. They were the types we looked for and then, as we've gone through the levels, it's become a bit easier. But because of where we are, we can never sign the at-the-level player. We can't compete with those terms and we have to be creative with who we bring to the club and where we look for our players.
Jamie Hopcutt: I got released [by York] when I was 18 and spent a few years around the non-league in England and had a few trials at clubs. Then one day I got an email and it was a trial day for Ostersund. I knew the manager from York so I thought I'd give it one last chance. I went to the trial and managed to do well - and a month later I was out in Sweden.
It was a bit scary at first. I was 19, leaving home for the first time wasn't something I was used to. The club wasn't so big - maximum 1,000 people watching - but it soon took off. That first year we got promotion and after that there was a big change in the love of football over here and it's grown and grown.
Hopcutt helped Ostersunds FK achieve promotion to the Allsvenskan - the Swedish top flight - for the first time in 2016. During their debut top-flight season he was joined at the club by another Englishman, former Middlesbrough academy player Curtis Edwards...
Curtis Edwards: I left Middlesbrough when I was 19, my contract ended. I went on a few trials at Hibernian and Bristol City but it didn't work out. I was stuck working with my dad on a building site and I got a call from a friend who was playing division three in Sweden (with Ytterhogdals) wanting to know if I wanted to get back playing. I spent one year there and then Graham called me and I went on a trial match and the journey has just gone up, up and up.
You miss your family a lot and you wish they could be here every week to support you, so that's hard. At this club there's a lot of people like that who have come from different parts of Sweden and are alone. It's tough. It's not what English lads usually do. It's definitely made me grow up as a person and I'm glad I took the opportunity.
Ostersund FK is not an ordinary football club. Their extraordinary achievements on the pitch are underpinned by a unique approach to team-building off it. They have developed a 'culture academy' where players sing, dance and act in front of an audience in an attempt to boost their performance ability. This has included staging a rock concert, at which Potter himself sang, and a performance of Swan Lake...
DK: It was a young lady who called me with the idea that cultural expression can be good for athletes. I thought it was very interesting - out of the box.
We let the players and staff consume culture, organising workshops with theatre, dance, singing, book reading. In our culture academy, we have a different theme every year. It is a training method for decision-making and bravery.
GP: We had to get players who weren't proven, get them into our environment and make them better. They play football for a couple of hours and then they're human beings for the rest of the time, so if we can help them in those aspects then it would be beneficial for them. We use it to help us win football matches fundamentally - but there's knock-on effects that it can develop the person in terms of self-awareness, in terms of motivation, in terms of empathy.
You start to find out about people in a different way. You can see who is more comfortable in uncomfortable situations, how they respond to that and how you can work with them and help them develop. Some interesting projects.
I can't say I'm a good dancer or singer, but I've done things I would never have done. I'd have never danced on a stage, that's for sure, or sang in front of people. I call it singing, it's probably nothing like singing.
We go out and integrate with the community in lots of ways. The most important thing at a football club are the supporters. We started with 500-600 people at the game, most of whom wanted you to lose to start with. Now we're averaging 6,000 and there's a real feeling in the town.
JH: The first programme we did was a theatre play - that was a bit daunting, trying to act in front of people. The next one we had to write a paragraph in a book about our journey which was quite cool. Then we went on to painting, dancing and singing - that's not really our strong point but we've got through it as a team and it's brought us together.
In their debut top-flight season, Ostersund FK finished eighth. They also claimed their first major trophy, winning the Svenska Cupen (Sweden's main cup competition) by beating reigning champions Norrkoping 4-1 at their own ground, the Jamtkraft Arena...
GP: It was a really special day, a full house. For us to host the Swedish Cup was incredible. To play Norrkoping, who the year before were champions, was a big moment for us.
DK: We are not here to be mid-table. That is terrible. Being fourth is the worst position you can be. Second is not good enough. We are here to be champions.
Then we get a ticket straight to the Champions League. That's why we took the cup - it was fantastic. It was great and it got us into Europe.
The cup win meant qualification for the Europa League and there they have reached new heights, making good on the plan Kindberg and his colleagues put in place back in 2010. That amazing night in Istanbul, when they beat Galatasaray, the highest-ranked side in Europa League qualifying, has been followed by victories over German side Hertha Berlin and Zorya Luhansk of Ukraine and a draw with Spain's Athletic Bilbao - a game in which they led until the 89th minute. They missed out on top spot in Group J to Bilbao only on goal difference but qualified to set up Thursday's last-16 tie with Arsenal...
GP: We were fortunate in that we probably played Galatasaray early in their preparations - new coach and going through some transition. We played well in Sweden, we scored a late goal, Jamie Hopcutt scored a good goal to make it 2-0. Then we had to go to Istanbul and get a result. At the end of the game their supporters were obviously irate at their team, but they started to clap us and we did a lap around Istanbul. That was a wonderful moment which started off the journey.
We won in Ukraine and beat Berlin here. We did well against Bilbao. We've got a long way to go - but it's really exciting.
JH: When I came, I heard about the vision of getting to the Allsvenskan, the top league and getting into Europe - people were just laughing at the chairman and saying it's never going to happen.
CE: The results that we've been getting, you must believe now that it's not luck. It shows we have a really good team here obviously if we can keep everything together.
Everything changes but the manager seems to keep going every year.
DK: We have a turnover of £5m. To beat a team like Galatasaray who have a turnover of £140m, that is impossible. It's 28/29 times the turnover. It's not possible but it happens in football because we can beat the numbers game. It's not about the money here, it's about the other stuff.
It's not about the money, it's about the other stuff. Ostersund FK is not just a remarkable football club, it is a family - one the entire city has now taken to its heart. They are also reaching out to other parts of the world, forging a partnership with Darfur United Football Club, a team made up of players from the Refugee World Cup, which was held in the Swedish city. In addition, each month a percentage of salaries are donated in order to support around 100 students and coaches from Darfur.
DK: With these projects we are doing, we think it's important to contribute to the world, to society, to help people.
It will make people be strong - stronger as a character because if you help people and understand how they are, that gives you a lot as a human being.
Six and a half years after being advised to go home, Potter and his family have established a happy life in this remote part of Sweden...
GP: A lot has happened here. Two kids have been born here, my eldest is at school. It's a place that will always have a special place in my heart. It's a wonderful place, a wonderful football club and fantastic people - so I'm very fortunate.
Regardless of me and my wife, we have to have a family feel, we have to look after each other. We're a tight-knit group because we're here in Ostersund - the next town is two and a half hours away. You're a footballer for a couple of hours a day - then you've got to be somebody's husband, somebody's friend.
You go to the town and you see people wearing Ostersund hats and scarves. You go to a soccer school and you see 60 or 70 kids playing and before there would have been nothing.
People want you to talk about it and you're forced to. Then when you do, you think: "Wow we've done a lot here." Three promotions, a major trophy, into the Europa League and we're still competing at the top of Allsvenskan in only our second season - so it's been amazing.
When I first came here, the record attendance was 4,000 and that was for motorcross - on the snowhills on the pitch. Now there's a real feeling for football.