Growing up, actor Kiefer Sutherland “wasn’t aware” of his father Donald’s success.

And it was only when he moved to Hollywood to pursue his own career, aged 17, that he realised what a “special and great” actor his father was.

“I phoned my dad and I said, ‘I feel so terrible,'” Kiefer says, in an interview being shown on BBC Two’s Lives Well Lived programme at 18:00 GMT on Sunday 29 December.

Donald Sutherland, who appeared in more than 200 screen roles, died in June, aged 88.

“So I’m 17 years old, I’ve moved to Los Angeles and a friend had this incredible collection of all of my father’s films on VHS [Video Home System],” Kiefer says.

Over two or three days, the teenager binge-watched his father’s work.

“When I see his work, it’s just astounding,” Kiefer says.

He told his father: “I didn’t realise how special and great you are as an actor.”

“And he was so sweet – he kind of almost cried and said, ‘Well, how could you? You were just a boy.’

“And that was a really special moment for both of us and our relationship kind of took a turn at that point.”

When the pair later worked together, on 2016 western Forsaken, “It was a great time to spend together,” Kiefer says.

Set in 1872, Forsaken, focuses on embittered gunslinger John Henry Clayton’s return to his hometown and his attempts to build bridges with his estranged father.

Their on-screen characters are in fierce conflict – but the off-screen relationship between the two actors was harmonious.

“I just loved watching him do his thing,” Kiefer says.

Known for an array of major parts, including in The Dirty Dozen, M*A*S*H, Don’t Look Now, Klute and Six Degrees of Separation, Donald Sutherland was not always destined for an acting career.

From a small fishing village in eastern Canada, he was part way through an engineering degree at the University of Toronto when he quit and went to England to follow his dream of becoming an actor.

“The courage to do that is extraordinary,” Kiefer says.

An early appearance on British television came in a 1960s production of Hamlet, with a young Michael Caine.

But his big break was in The Dirty Dozen, in which, at first, he had a non-speaking part but was picked for something far bigger, apparently at random, by director Bob Aldrich.

“He didn’t even know my name,” Sutherland said.

“We’d all had our hair shaved off. He looked around the table and he said, ‘You with the big ears, you do it.'”

Kiefer describes this as “a real breakout moment for my father”.

But the fact he then “managed to be in films that were incredibly important each decade, is a testament to his capabilities as an actor – and I’m incredibly proud of him for it”, he says.

Never nominated for an Oscar, Donald Sutherland received an Academy Honorary Award in 2017 for his lifetime contribution to cinema.

“His love and his humour and his kindness were huge,” Kiefer says.

“He had, I think, superhuman skill as an actor and it’s wonderful to have it.

“I’m very lucky as a son, you know, to be able to throw on a film and, you know, get to see my dad.”

Lives Well Lived is on BBC Two at 18:00 GMT on Sunday 29 December.