ADAM Robertson isn’t just an actor. He’s a living example of the Nietzschean adage (which he no doubt borrowed from the Kelly Clarkson song title) ‘What doesn’t kill you makes you stronger’.

Growing up in Thurso, the former River City star had been bullied, abused by his alcoholic father and teachers. (“One teacher would pick me up by the ears and slap me hard.”) He was on first name terms with the members of the Children’s Panel and social workers had his file committed to memory.

Right now, Robertson is starring in Oran Mor play, Cool Dads, a tale of touchline fathers who are living their lives via extension of their football-loving schoolboy sons. But he flashes back on his own often tragic schooldays.

“We moved from Edinburgh when I was three. We were outsiders, incomers, and I never fitted in. Then when my parents (his dad is a glazier) broke up, life for my mum, me and my brother was about council flats, benefits and even living in a caravan for two years.”

He adds: “My dad was an alcoholic. We have a good relationship now but back then he was a violent drunk.”

The schoolboy was singled out by his peers. “I got bullied because I wore sh**** trainers, clothes from jumble sales, that sort of stuff. Meantime, I hated the teachers, and with good reason. One would pick me up by the ears and slap me. And make me do push ups in the class to humiliate me.”

Robertson became a school rebel. A classic cry for attention. An involvement with breakdancing (“the lino on the pavement, the lot”) helped but by the age of 15 schooldays were over, replaced by work in a freezer factory.

But what stopped the move to a young offenders’ unit was discovering surfing, going on to become a Scottish junior champion. “It got me out of Thurso,” he says in thankful voice. “Now, I could see a world outside and at 17 I took off to Cornwall, to surf, while working in Burger King cleaning the broiler.”

He didn’t make it as a pro surfer and moved back to Thurso, to clean floors at Dounreay. But he new he needed more. “I got myself down to the Job Centre and looked down the alphabetical list of careers. My eyes stopped at ‘P’ when I saw the words Performing Arts. I thought ‘I could do that. I like stories. Reading. I had liked breakdancing.’

Yet, Robertson had never been inside a theatre in his life. He’d never read a play. How to progress? He went back to school to see the “really nice Mrs Omand, the English teacher, who had once been so encouraging of his poetry reading.

She gave him plays to read and steered him in the direction of the Dundee Theatre Arts course, a one-year foundation. “I kicked the a*** out of it.,” he remembers in delighted voice. “I’d go to see plays such as Who’s Afraid of Virginia Wolf, with David Tennant starring, seven times. I soaked it up.”

Robertson’s resolve was tested when accepted by the Drama Centre in London. He had no money to pay the fee. “Amazingly, the Drama Centre let me start, with no fees up front. Meantime, I slept on a floor in the East End. I would have starved, but for Sir Anthony Hopkins, who was Patron, paying for my hot lunches at the canteen.”

Then fate kicked in. A Welsh benefactor offered to pay a struggling actor’s fees for a year. It kicked in again.“I went along to see a free theatre show one night in Islington. A special guest sat next to me, who turned out to be Richard Wilson.” At the end of the night Wilson not only offered to pay the young Scot’s fees he later added £400 a month for subsistence. “I think he could see I was as skinny as a rake.”

Robertson, who lives in Glasgow with wife Anna and their two sons, went on to find acting success in a range of theatre roles, playing the hunky doctor in River City from 2011.

Does the actor believe life has tested his own resolve, his acting training the reward? “Yes, I do.” He adds, smiling; “Don’t get me wrong. Acting can be a tough life. Last year I was driving an Uber, to pay the bills.”

Yet, is there delight in knowing the hated teacher, who once lifted him up by the lugs may have seen him on TV, perhaps in theatre? “He said to me ‘The only place you’re going to end up is prison, Robertson.’ Well, I did end up there. But teaching drama to young people. In some way that teacher’s malevolence helped push me on.”

Cool Dads also features Natali McCleary, Kris McDowall and David McGowan, Oran Mor, Glasgow, until Saturday