Picture the scene. You're sitting opposite Morgan Freeman in a plush London hotel room. He's dressed in a sharp grey suit and tie, with an inconspicuous gold loop earring hanging from each lobes. He fixes you with one of those trademark becalmed beatific stares. “You,” he says, in the mellifluous baritone that's carried him through roles as dignified as the United States president (Deep Impact), God (Bruce Almighty) and the avuncular mentor we all wish we had (everything else). “Are, going, to, die.”

It's not the cheeriest start to an interview, but we run with it. “If you don't die, then you can't live,” he continues. “Life feeds on its own existence, you only live to die.”

From anyone else this might sound like New Age claptrap, but from the kindly eyes and softly smiling mouth of Morgan Freeman it is aching existential reality. If he starts a religion tomorrow, I'll be the first at the altar. But today death is on the mind of the 70-year-old Oscar winner mainly because it's the ostensible subject of his latest film, The Bucket List.

The movie is a tearjerker starring Freeman and Jack Nicholson as two septuagenarians who compile an urgent list of unfulfilled ambitions and whims (get a tattoo, go skydiving etc), to be experienced before they succumb to cancer. At times whimsical, at others mordantly witty, it is unapologetic in its depiction of trauma. A lot of early screen time is devoted to vomiting, night sweats, operation scars and burst catheters.

“Sometimes you want to upset an audience so you can engage them,” says Freeman, who also narrates the movie with the gravitas that proved so effective in The Shawshank Redemption and Million Dollar Baby. “I've done so-called Hollywood films, and I know that it's all about wanting the audience to feel upbeat, give them a happy ending. But they also like complete stories. If your story's complete it doesn't have to have a happy ending.”

Freeman knows exactly what he's talking about (and if he doesn't, well, he sounds as though he does). Along with Gene Hackman and Clint Eastwood he is one of the few actors in youth-obsessed Hollywood to have capitalised on the ageing process. This year alone he will star in five movies, including the summer blockbusters The Dark Knight and Wanted, with three more already slated for early 2009, most notably Eastwood's latest, The Human Factor. “I don't have to work,” he says, explaining that his life now revolves around trying to improve his golf and relaxing in his own blues club in Clarksdale, Mississippi. “I could stop and never have to worry about paying the rent. I'm working for the joy of doing it.”

And yet you look at Freeman's soothing countenance, you feel his joy, and you wonder: where are the cracks? How did this equanimity get to be so intoxicating? And if this is the ecstasy, where is the agony?

There are hints, like all things, in the past. He was born in the racially segregated South, in Memphis, Tennessee. He lived briefly with his mother in the rough and violent South side of Chicago, one of five children sired by four different fathers. He describes his childhood as something that had to be endured, rather than enjoyed. “I didn't find the big city to be that much fun,” he says. “It was fraught with stress. You had to belong to a gang or otherwise you were in deep doo-doo.”

After high school he joined the newly desegregated Air Force, hoping to become a pilot. But after nearly four years as a radar mechanic, and disillusioned with an Air Force that wasn't actually that desegregated, he moved to Los Angeles and studied drama.

His acting career moved forward fitfully. There was a Tony Award in 1978 for his part in The Mighty Gents on Broadway, and a string of off-Broadway Obies during the Eighties He also became known as the kids' TV staple Easy Reader, a spelling-obsessed jive turkey in the Sesame Street precursor The Electric Company. When he finally emerged, in 1987, into the limelight, with an Oscar nomination for the role of the terrifying pimp Fast Black in the movie Street Smart and a Tony award for the Broadway smash Driving Miss Daisy, he was already 50.

I wonder if he looks back at the many injustices and hardships of those first punishing 50 years, and is filled with righteous indignation. He half-smiles. “It's like anything else,” he says. “If you wake up and the snow is knee-deep outside, you are not filled with rage. It's just something that you've got to cope with. If you're living in a situation it's the only situation that you know, and you've got to deal with it.”

There were low points nonetheless, and he often drowned his disappointments in alcohol. In the Seventies especially, while his work on The Electric Company was paying the bills, it wasn't nourishing his soul. “I felt like a prostitute,” he says. “I was working not because I enjoyed the work, but because I needed the money.”

His period as a boozer ended, he says, when he woke up face down in a doorway, unable to remember how he got there. “I recognised that it had become a problem, so I just quit,” he says. “I do have self-control. Once I realise that I've got to change something I just do it.”

These days, the Freeman that followed his Street Smart breakout - the Freeman of Unforgiven, of Seven, of Amistad, and so on - is something of a homespun demigod. He says that success hasn't changed him at all - apart from the 120-acre Clarksdale estate, the Cessna airplane, the yacht in the Caribbean and the friendships with Sidney Poitier and Nelson Mandela.

There is a key scene in The Bucket List in which Freeman's character is approached in a bar and boldly propositioned by a delectable young woman. I ask whether he ever experiences this in real life. “Yeah, you get approached quite often, but it's strictly a compliment,” he says, smiling to himself, and reassuring us of his loyalty to his wife of 24 years, the costume designer Myrna Colley-Lee (with whom he has two children, plus two from a previous marriage). “You couldn't possibly try to entertain all of the people who, er, seem to be offering you entertainment. Because most of them want some compensation for it.”

He says that he's excited about The Human Factor. It's about Nelson Mandela (Freeman holds the rights to Mandela's autobiography Long Walk to Freedom), the 1995 Rugby World Cup, and the South African president's pivotal role in securing his country's victory. “It's about how he managed to manipulate the whole event,” Freeman says, grinning.

In the meantime, he says, he's very much content with his station - with his golf swing, his career, and even with the inevitability of his own demise. “The American Indians have this saying,” he explains. “‘Look at the day, look at the sunlight, the grass and the trees! It's a good day to die!'”

He gestures to the unseasonably bright blue London sky, and adds slowly, sweetly, as only he can: “This is a great day to die.”

The Bucket List is released on Feb 15

Explore Film

• Film Reviews

• Trailers

• DVD

• London Film Festival

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010