Gary Oldman: From Sid to Smiley, why it’s not more Mr Nasty for Best Actor Oscar nominee

We predict of him as Sid Vicious of the Sex Pistols in Sid And Nancy.

Then there’s Bex Bissell, estate agent by day and Stanley knife-wielding leader of a gang of football hooligans by night, in Alan Clarke’s The Firm.

Even as Sirius Black, godfather to Harry Potter, he’s dangerous, teetering at the fringe of an explosive temper.

But in person, four-times married Oldman, 53, is de facto a totally nice chap. He was showered with praise for the Smiley role.

In it, he holds his own against co-stars John Hurt, Colin Firth and Benedict Cumberbatch.

He even eclipses the formidable Sir Alec Guinness, who played Smiley inside the acclaimed Seventies TV series. ‘I loved it because for when I was not being asked to dance off the walls like a nutter,’ he says.

‘It was about blending in, like a true spy. Smiley is an observer.’

James Bond he certainly isn’t. ‘I needed to wear somewhat of weight for Smiley,’ he says.

‘i might basically eat anything. What I hadn’t calculated was how hard it’s to lose.’

Did he find the offer to play this banal sixtysomething spy somewhat disconcerting? ‘Mel Gibson once noted me as Mr Potatohead,’ he says.

‘As in, you place the entire various things on and make him look the way you want. However it’s easy for him to mention, the great-looking b*****d.

‘And i’m now what you will technically call an out-of-work actor. I actually have nothing to move directly to.’

Except, obviously, the Oscars.

• Tinker Tailor Soldier Spy is out there on DVD from January 30.