His Inverclyde accent is undetectable as he plays incorruptible DS Steve Arnott in the BBC hit drama series Line of Duty.
But Greenock-born actor Martin Compston has revealed the need to sound like a Londoner for so long while filming means he even dreams in the voice of his on-screen character.
I’m under no illusions of how privileged I am - I’m lucky to be in a job that I love and I’m paid well to do itMARTIN COMPSTON
Compston, 34, is known to keep to Arnott’s accent for months on and off set while filming each Line of Duty series.
The show has become the biggest TV programme of 2019 across all channels, with the first episode of the new series receiving an audience on television and online devices of 11.4 million.
Speaking on BBC Radio Scotland’s Stark Talk tomorrow, Compston said: “I’m not [very good at accents]... but that makes me work my a*** off to do them.
“I’ve always had a good work ethic. I get so over-prepared so I’ve got no excuses on the day.
“You know you’ve nailed it when you wake up in the morning and you’re talking to yourself in the accent.
“Your mind just goes to it. You have dreams in it, for sure, because you’re doing it that much.”
Compston has become a familiar face on TV as well as the big screen since he was discovered as a teenager by filmmaker Ken Loach for the leading role in Sweet Sixteen.
Recent film roles include Lord Bothwell in Mary Queen of Scots, alongside Saoirse Ronan and Margot Robbie; and Burnham in The Aftermath, with Kiera Knightley.
Now living in Las Vegas with American wife Tianna, whom he married at Mar Hall in Renfrewshire in 2016, Compston said he had fulfilled a lifelong dream, by buying a house with a swimming pool.
He said: “I’m under no illusions of how privileged I am - I’m lucky to be in a job that I love and I’m paid well to do it, but I’ve never been flash.
“I’m not in to big cars or fast cars or fancy clothes so I’ve kind of been lucky and saved my money, so we were able to buy our dream home.
“I’ve got a swimming pool out the back. It’s hard to say this stuff and not sound like a you know, but it’s been a dream.
“I’ve got family in Dunblane and they had a pool, in Dunblane, but we used to go and spend our bank holidays and stuff at their house and jump in their pool and I can remember growing up and thinking one day I want a pool. It’s always sort of been my dream.
“So my wife got everything else she wanted but that that was my one thing I wanted.”
l Compston will once again swap his waistcoat for a football kit as he takes to the pitch for this year’s Soccer Aid tournament later this summer.
He is reclaiming his position in the Soccer Aid World XI squad in the annual event, which sees celebrities and ex-professional footballers join forces in aid of Unicef.
Compston will play alongside Usain Bolt, singer Niall Horan and former Chelsea striker Didier Drogba.
They will face the England squad including Olympic champion runner Sir Mo Farah at Chelsea FC’s Stamford Bridge on 16 June.