Muhammad Ali is universally revered, as a boxer and as a human being. Pretty much any list of the biggest stars in sporting history will have Ali in top spot, the "greatest of all time", as the man himself would say.
Yet this is also someone who could crudely mock another black man by waving a rubber gorilla at him. Ali taunted his fellow boxer Joe Frazier: "We're in Manila. Come on, gorilla; this is a thrilla."
The bout that ensued – Ali-Frazier III, the Thriller in Manila of 1975 – was perhaps the most brutal, and some say the best, boxing contest ever seen. Such was the resistance of his old adversary that an exhausted Ali, who finally won when Smokin' Joe was judged by his corner to be unable to come out for the 15th and final round, described the fight as "the closest thing to dyin' I know of".
To the victor the spoils, and Ali has been lionised in film, from the 2001 Hollywood biographical Ali, starring Will Smith, to the Oscar-winning 1996 documentary When We Were Kings, which captured the magic and the madness of the Rumble in the Jungle, when the mighty George Foreman was mesmerised by his opponent's elusive rope-a-dope trickery. Frazier had to be content with having a boxer play his character in his great rival's biopic.
Now, the Thriller in Manila has been given the documentary treatment by Darlow Smithson, the British production company behind the phenomenally successful mountain-climbing film Touching the Void. And it is not simply another paean to Ali but, in the words of the executive producer John Smithson, it attempts to "tell the story a little bit more from Joe Frazier's point of view".
Frazier, now 70, was filmed at the boxing gym above which he lives in a run-down quarter of Philadelphia. He has lost none of his presence. "Meeting Joe was like meeting a rock star, like meeting Keith Richards," says Smithson. "He had a real quality to him, a dignity. One can argue that history has been pretty kind to Muhammad Ali, who is an utterly remarkable sportsman. But has it been as kind to Joe Frazier?"
The 90-minute documentary, which is directed by John Dower (who made Once in a Lifetime, a documentary on the New York Cosmos football club), shows the old warrior watching footage of the original fight in the Philippines. Amazingly, he had not seen it before. "There's incredible pathos when you see Joe looking at the fight," says Smithson. Dower and his team were given enthusiastic assistance by Marvis Frazier, Joe's son and an accomplished heavyweight boxer. Even now, Smithson is not sure whether Ali's taunting of his opponent was merely a pre-fight stunt or something more telling. "I remember seeing Ali interviewed by Michael Parkinson. I loved Ali, but you see him in a different light here."
Smithson said he "didn't want a sports film but something that would appeal to a wide audience", and to women as well as men. "This film is about more than boxing," he says. "It's about race, religion and politics."
Thriller in Manila is the gala screening at this year's Sheffield Doc/Fest, but behind the excitement Smithson is deeply concerned for the future of theatrical documentaries, a genre from which so much was expected following the success of Touching the Void five years ago.
"Touching the Void was the most successful British documentary in box-office history. We had all hoped it would be the start of a wonderful new world," says Smithson. "No documentary from the UK has come close to emulating that success. Instead, there have been a real lot of bad documentaries that should never have been made." He declines to name names, but he was clearly less than impressed by the overall standard of entries at this year's prestigious Grierson Awards, where he was judging the theatrical documentary category.
Next week, Smithson will take part in a panel discussion at Doc/Fest called Theatrical Docs RIP. It is, he admits, "a slightly provocative title". But for Smithson, getting a documentary into the movie theatre remains the real thrill. "To get it into a cinema where people have to pay to see it is the ultimate challenge as a documentary maker," he says.
'Thriller in Manila' is the gala film at Doc/Fest on 5 November and will be shown as part of the 'True Stories' strand on More4 on 11 November at 10pm