Peter Morgan, the Oscar-nominated writer of Frost/Nixon, was the exception, just as he was with the monarch in The Queen and with Brian Clough in The Damned United.
The latest object of the British writer's attentions is James Hunt, whose Formula One world championship winning year of 1976 is celebrated in a new movie, Rush. Directed by Ron Howard, who also worked with Morgan on Frost/Nixon, Rush homes in on the rivalry between the British victor and the Austrian triple-champion, Niki Lauda.
"It's something you have to do," says Morgan, 50, of filling in the gaps between public and private when it comes to a biopic. "It's something Ron and I confronted with Frost/Nixon as well, and The Queen. Did they actually say this to one another or that to one another? As soon as you are going off matters of public record you do have to rely on a writer's imagination."
The public image of Hunt is well known. The playboy racing driver whose overalls sported the legend, "Sex, the breakfast of champions", Hunt did indeed live fast and die young, 45 when a heart attack claimed him in 1993.
When Morgan was first approached to write about Formula One in its 1970s heyday, one possible subject was Scotland's Jackie Stewart. Morgan, however, couldn't see it.
"It's an instinctive thing. When you make a choice as a writer about what it is that you want to write, and what it is you are going to spend six months thinking about, you have to fall in love. I just didn't fall in love with the idea of Jackie Stewart. He is a great champion, but I just didn't feel there was stuff there I wanted to write about or that I could emotionally connect with."
Morgan had a further difficulty in writing about Formula One in as much he was not a fan, to put it mildly. "I don't understand it," he says, with a laugh. But in the story of Hunt and Lauda (played by Australian actor Chris Hemsworth and Daniel Bruhl respectively) he had a yin and a yang, the glamorous, hard partying Brit versus the cool, calculating Austrian. It is the sort of mano-a-mano territory on which Morgan has planted his flag before.
In Frost/Nixon the interviewer took on the US president over Watergate; in The Queen, the monarch appeared at odds with the country over the reaction to the death of Diana; in The Deal it was Gordon Brown and Tony Blair duelling over the leadership of the Labour Party.
"I can't seem to escape it," says Morgan when asked what draws him to such two-headers. "When I try to do something else critics are really vicious. I have been really beaten up every time I have stepped out of my little box, which hasn't made experimentation any easier."
He did indeed take a critical pasting over 360, a star-packed roundelay featuring stories from across the globe ("An over-plotted and dreary farrago" said the Los Angeles Times), and Hereafter, the Clint Eastwood-directed drama about life after death ("If you did get to the afterlife you'd hope they weren't playing this movie," said Time Out).
Besides coming up with his own stories about rivalries, he is sent many more. "I keep trying to spin it in a different way but I do seem to lock into these stories."
Rush appealed to him not just because it was great drama, though there is plenty of that, including Lauda's crash at Nürburgring, after which he was given the last rites, and Hunt winning the World Championship by a point.
The London-born Morgan also had a connection to Austria through his Austrian wife, and he already knew what a great character Lauda was.
He went to see Lauda in Ibiza and they talked for hours. Morgan slips into a flawless impersonation of the comically deadpan Lauda. "I just love the way he talks. I said, 'Did you like anybody in Formula 1?' 'No.' What were they like? '***holes'."
It was through talking to Lauda that Morgan was able to put himself into the mind of a racing driver. Admitting to "no understanding of cars", it was Lauda who explained to Morgan the basics and set out the stuff only a driver would know, such as "reading" an engine through the car seat.
"When he talks he distills things to their essence in an unbelievably riveting way. There is no such thing as a dull conversation with Niki."
Morgan showed Lauda the rushes as the film progressed, and it soon became clear this was going to be an emotional experience for the Austrian, particularly when it came to the accident, and how people reacted to his subsequent disfigurement.
"He was tearful, very tearful, when he first saw it, he was really shaken. And he is tough to shake."
Danger did not end in the 70s - as the deaths of Ayrton Senna and Roland Ratzenberger in 1994 showed - but this era is widely judged to be the heyday of men being men and cars being hairy to drive.
"None of us wish anybody ill but something is missing from the sport in that it feels like, it presents as, a dangerous sport, but it actually isn't any more," says Morgan. "You can go into the pits and it doesn't even smell of petrol."
Morgan may not have been a petrol head when he started Rush, but he found the film having an effect when he bought a new car: something large, second hand, with a big petrol engine. "There's an Opec crisis every time I start the engine. I spend my life in petrol stations."
Though not a natural fan of Formula One, even he has been amazed at how thrillingly Howard and his team bring the races to life. "It doesn't feel like a low budget film, but I can assure you it was. It was pretty rough and ready."
As the film comes to a close, captions fill the audience in on what happened next in the lives of Hunt and Lauda. In Hunt's case, it is a poignant, still moment in an otherwise helter-skelter movie.
"There's a darker movie to be written about James but that wasn't 1976," concludes Morgan. "That was his glory year."
Rush opens in cinemas on September 13