AS Fiona Rintoul flicks through the pages of the Stasi files that documented her time in East Germany, it is fair to say her student experiences were different from most.

While working on a modern languages degree at the University of St Andrews in the 1980s, she spent a term at Leipzig, then behind the Iron Curtain, where the movements of Fiona and her fellow students from Britain were routinely reported back to the authorities.

"To me it was a very exciting experience. You were going into a different world, which is something that's not really possible any more," she remembers. "I was aware of being watched. There were people among the interpreters and translators we worked with who were definitely watching what we did.

"Because they were students, I think they were almost trainee spies and they were a bit amateurish, so sometimes it was really obvious."

Now nearly 30 years later, her time as a 21-year-old in East Germany has inspired her first novel, The Leipzig Affair, the fictional account of a Scottish student in the German city who unwittingly becomes the cover for a local girl's attempted escape.

Deftly told in short, punchy chapters, the thriller is a page-turner that shifts from East to West and the dark days of the 1980s to present reunification. Its release coincides this weekend with the 25th anniversary of the fall of the Berlin Wall.

Fiona, who grew up in East Kilbride and now lives in the West End of Glasgow, says she drew on many of her own experiences in the 1980s for background to the storyline, painting a picture of long queues at the Post Office to get a line out to phone home and applications for exit visas to leave the country.

"I went with two other students from St Andrews University and I remember we were at the border and all suddenly felt a little bit scared. There were guards coming through the train with sniffer dogs," she recalls.

"You got used to it. All these dictatorial regimes are full of paper tigers, and once you got used to how things were I was never scared again.

"It was very exciting to be in this different world and very interesting as well because people were different - they had different values and sensibilities, and they had been socialised in a completely different way.

"And although there were problems with that, there were also things about it that were quite appealing to someone coming from Thatcher's Britain, where three million people were unemployed and the country was at loggerheads.

"The commercial imperative wasn't there and that in some ways was an appeal. It was very drab, very grey, very rundown.

"You stop noticing after a while, and there was something quite appealing about the rundownness of it all. It wasn't ruled by money."

The Stasi files on Fiona and her friends covered their East German minders in Leipzig and their comments on politics in the Soviet bloc.

As part of the research for her novel, she used extracts from the documents recorded on a woman she later met who had been a prisoner in the secret Stasi prison.

She says the idea for the book has been in her mind for many years, solidified after she returned to Scotland from London to study for a creative writing MLitt at the University of Glasgow. Then, while working as a financial journalist, she spent her spare time fine-tuning the story.

She still visits Germany and says as time has passed the two parts of the country have come together.

"Angela Merkel is an East German, the German President Joachim Gauck is an East German. There was a while when it felt like all the top positions were held by West Germans and they looked down on them (the East Germans) and laughed at their funny accents and the fact they couldn't speak English well but that is changing," says Fiona.

"The worst time was probably the 10 years after the wall came down. When I went back to Leipzig and Berlin in 1997 when I was doing an exchange programme a lot of people said to me, 'It was better before'.

"They were very disillusioned and felt it had been a kind of takeover. You could see why they felt like that because they did roll in and change everything and make everything West German.

"Roland Jahn, a dissident journalist who was thrown out of the GDR, literally bundled on a train and then taken to West Berlin and chucked out and told never to come back, is in charge of the Stasi files now. He was making the point that there was a big difference between the East German state and East German society.

"People lived in this country and tried to make a life for themselves, tried to make the best of it, and so they had an affection for that life, as you would expect.

"It was very disorientating for people to suddenly be in this society that had different expectations."

l The Leipzig Affair by Fiona Rintoul, Aurora Metro Books, £8.99. The book is launched at Waterstones, Sauchiehall Street, Glasgow, on Tuesday.