RETURNING to academic studies as a mature student is no longer unusual.

Colleges and universities welcome older people with open arms, as do the students who are on a more conventional academic journey.

I know this because I returned to university myself three years ago.

I admit I was apprehensive. When I attended for interview, I was a little unnerved when I found that my vetting session comprised me and five others young enough to be my children.

But I needn’t have worried. Our cohort of 30 was a happy blend of ages and we all got on brilliantly. I wasn’t even the oldest student on the course!

Brian Mackinnon, however, took returning to academia to a whole new level.

Under the guise of Brandon Lee, the Scot from Bearsden returned to his form secondary school at the age of 30.

A new film, which premiered last week at the Glasgow Film Festival, retells the story of how Mackinnon, claiming to be a 17-year-old from Canada, enrolled as a fifth-year student at Bearsden Academy, near Glasgow, in 1993 and gained five A-grade Highers.

It was a year later, while he was a medical student at Dundee University, that his double life was exposed by a newspaper and Mackinnon was thrown off the course.

The film My Old School was written and directed by Jono McLeod, who was a 16-year-old classmate of Mackinnon – or Brandon, as he still calls him.

McLeod told BBC Scotland that he does not think Brandon meant to do any harm and he has interviewed other classmates and teachers for the film who agree.

“A lot of people in the class have their own take on what Brandon did but for the most part they have a fondness for him,” he said.

“I know that’s not across the board. The film is not a take-down of him but I don’t agree with all the decisions that he made back then.”

McLeod explained that Brandon agreed to tell him his story but didn’t want to be seen on camera.

So the 58-year-old present-day Mackinnon is played by Alan Cumming, who lip-syncs to the words of the real-life interview.

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MacKinnon has previously described how he first left Bearsden Academy in 1980.

He went on to Glasgow University but was excluded after failing exams. Mackinnon claimed he had been unwell at the time but the university maintained the correct procedure had been followed. He said he was devastated when he was thrown out.

“I felt as if I had been robbed and cheated out of my place at university,” he told The Herald in 1995.

In an interview with BBC Scotland soon after he was exposed, Mackinnon told how he had enrolled at the school at the age of 30 by presenting two items of “bogus documentation”.

These were a false letter from his father – who he claimed was a professor – and another from a tutor in Canada. He also claimed his mother was an opera singer who was touring the world and that he had returned to Scotland to live with his ailing grandmother.

And everyone bought this rather far-fetched story … from a guy with the same name as an American movie star.

Ten out of 10 for effort, Brandon.