He is sitting in the back room of a sheltered housing unit in Leith recalling snapshots of his previous life when he was young and fearless.
In this place, Ken Buchanan is just another resident, a man trying hard to free himself from the addiction to alcohol that is testing him more than any of the fearsome boxing greats he is now talking about.
There will be laughs about his famous days in the ring and there will be tears about the torturous complexity of his life now, the daily battle with drink that has consumed him for so long.
He says that there is a film being made of the life of one of his most colossal adversaries, Roberto Duran. Robert De Niro plays Duran's trainer, Ray Arcel. An Irish actor called John Duddy plays Buchanan.
He'd like to think he'll be able to travel to America for the premiere, but in his heart of hearts he suspects that's a trip too far now.
He says: "I tell young guys and young lassies, 'Watch your drinking because, I'm telling you, it's killing me'.
"I speak to them in pubs. I say, 'Be careful, cut it down'. I was told myself that years ago. Now it's me saying to other people what I got told myself."
He transports us back to the most extraordinary places and recalls the most storied people, a parallel universe to the one he's living in. He tells the tale of the night at Madison Square Garden in December 1970 when, as world champion, he put on a boxing exhibition against the undefeated Canadian Donato Paduano that had gnarled New York boxing scribes comparing him to Sugar Ray Robinson in his pomp.
He talks of fighting on the same bill as Muhammad Ali, not once but twice, both times at The Garden. The second one was 1972, when Buchanan beat Carlos Ortiz.
"I cannae remember the guy Ali was fighting. Famous, though. Used to be world champion. Wasn't a huge guy. Big long face," he says.
The legend that was Floyd Patterson.
"The first time was when Ali fought Oscar Bonavena and I fought Paduano. I was top of the bill, I was world champion and Ali wasn't world champion at that stage. He hadn't won back the title yet.
"I had a dressing room and he didnae so Angelo Dundee comes up and says, 'Can Ali share your room?' and I said, 'Aye'.
"There was an ashtray with a piece of chalk in it so I took a piece of chalk and I bent down and I made a mark on the wooden floor across the way and when I got to the end Ali is standing there, saying, 'Hey man, what are you doing?'
"And I says, 'Muhammad, this is my dressing room, right? And I'm letting you share it'. He says, 'Yeah. What's the line for?'
"I said, 'That's your side and this is my side and if you dare cross that line...'
"I showed him my fist and he did that tight-faced thing and burst out laughing. I thought, 'Thank God, he saw the funny side, he's not going to batter me'.
"He beat Bonavena but it was a terrible fight and people were saying, 'If Buchanan hadn't been on the bill we'd' no' be going back there again'. That was my first time fighting in The Garden."
Buchanan turns 70 in June. September marks the 50th anniversary of his first professional fight as well as the 45th anniversary of him winning the WBA lightweight title against the great Panamanian, Ismael Laguna, in San Juan, Puerto Rico.
"We went to Puerto Rico and I did 15 rounds with Laguna in 125 degrees of heat at two in the afternoon," he recalls.
"Laguna was the champion and he thought I'd go down the Swanee dead easy with the heat and everything.
"He spoke to me years later through an interpreter. I met him at the Hall of Fame when I became the first living British boxer to get in there. He said that he expected me to collapse after eight or nine rounds.
"He said, 'When I hit the 11th and 12th I kept saying to my manager what's keeping him up?'"
The making of Buchanan? He remembers that, too. "I got bullied a wee bit at school, I wasn't a tall guy. I was middle-sized, dead skinny. When I won my first championship I was 3st 2lbs. I was eight years old. I stayed at Northfield in Edinburgh in these prefabs. I was the only one in my school who went to a boxing club.
"I had a wee bit of a chip on my shoulder only because guys wanted to fight me and when I knocked them down their brother wanted to fight me.
"I got picked on. I'd go to school and they'd start arguing with me and it was a left jab I gave them and that was it. There weren't many big scraps. It was just one punch. They never lasted long. But I always wondered why they were picking on me.
"Years later I met a couple of the guys that I'd fought and they said to me, 'My dad told me you were a boxer and I should have a go with you'. That never left me really."
In the two years between autumn of 1970 and autumn of 1972, Buchanan fought at The Garden five times. In his career he fought at the Miami Beach Convention Center, where Ali beat Sonny Liston in 1964, the Royal Albert Hall and the Cagliari football stadium.
He fought in South Africa, Japan, Italy, Denmark, France and Spain. He fought in Nottingham and Solihull, Hamilton and Port Talbot, Leeds and Glasgow and Aberavon.
And yet he never fought in his home town of Edinburgh.
He explains: "The Edinburgh people have always been fantastic to me, but the people who ran Edinburgh just weren't aware of boxing.
"I went to Murrayfield ice rink looking to stage a fight there but the guy couldn't give me a day. Would he not cancel the ice skating for one night? He says, 'No, no'. So that's a regret."
Sixty-nine professional fights and 555 rounds of boxing and yet so often it comes to one round in particular, the 13th against Duran and the late and low blow to Buchanan's "watcha-ma-callits" that ended that fight, albeit while Duran was well ahead on all scorecards on the night.
"He was a scrapper, Duran," Buchanan says. "I made the mistake of trying to go toe-to-toe with him. Stupid. I should have hit and run, hit and run.
|Ken Buchanan facts|
|Born in Edinburgh on 28 June 1945||Won ABA featherweight title in 1965 then turned pro|
|Pro record: Won 61 (27 by KO), lost 8||Won WBA world lightweight title in 1970|
|Held WBC world lightweight title in 1971 before being stripped of it over contractual dispute||Lost WBA title to Roberto Duran in Madison Square Garden in 1972|
"The second fight never came off. His manager says to himself, 'I can see what's going to happen here'. I was going to bob and weave and slip punches and move around the ring. The fight never happened."
He had other big days after Duran but many more grim ones. His marriage broke down, his house was sold, the hotel that he owned went, too. He had money and he was too trusting with people and he lost it.
He remembers the time he cashed an £800 cheque for a regular at the hotel bar and the cheque was a dud. He says if he looked out the window he could still see it bouncing. He never saw the guy again.
He has a massive fight on his hands right now. He knows it and makes no secret of it.
"I'm trying to control it, but I cannae all the time," he says of his drinking. "I think of one or two bad things that happened to me in my life and I should say 'No', but I just go and have a drink and that.
"I've been fighting it for years. It's not like it just happened last week. I've been fighting it for years. I know I'm probably an alcoholic.
"I'm trying my hardest. I'm just trying to keep drink out of my room and I cannae do it. I can't keep it out of my mouth. I don't know how long I'll last."
Hugh McIlvanney catalogued Buchanan's career better than anybody. In a piece from 1981, he wrote of the qualities that made him great: "It was conveyed most succinctly to this reporter in a conversation with Roberto Duran in Las Vegas long before the Panamanian had discredited himself against Sugar Ray Leonard.
"Duran was reckoned then to be the fiercest man in the game and it was significant that when he was asked to name the opponent who had most impressed him the answer came in an instant growl.
"'Buchanan,' said with a conviction that was as close as he went to saluting an adversary.
"What Duran had seen at close quarters was something that even good judges were inclined to overlook in the young Buchanan. Many saw him initially as a richly gifted but rather too Corinthian, stand-up-and-prance-behind-the-jab kind of boxer.
"What they had to learn about him was that all the fine technique was reinforced by courage and remarkable hardness. He was an out-and-out fighting man."
Those are qualities the great man is going to need to find again as he faces his most lethal opponent yet.