All of this is conveyed in visceral detail: here at last is a movie that
actually comes somewhere near to explaining why people are obsessed with
cars whizzing around a track – and particularly with the races of that
period, with old-fashioned gears and steering requiring levels of endurance
hard to imagine now.

The motivating force of the movie, however, is the rivalry between Hunt and
Lauda, between the glamorous English playboy with no sense of risk and the
austere, brilliant Austrian who calculated the odds.

Peter Morgan, writer of The Queen and Frost/Nixon – which Howard
also directed – wrote the script after many meetings with Lauda. He was
impressed and fascinated by him yet at the same time, as a teenage boy
growing up in England: “I loved James Hunt. He was so sexy, anarchic and
beautiful.”

So the movie is a tribute to both men, to their on-track battles and off-track
respect.

But although Lauda has been closely involved with its making, he has allowed
his character to be portrayed in ways that are not entirely truthful.

For example, after Hunt’s victory in the Spanish Grand Prix – the first sign
that he might actually challenge Lauda for the title – it is Lauda who
reports the McLaren car for being an illegal width and gets him
disqualified. It was not; it was a member of the Ferrari
team.

Equally, when Lauda calls a drivers’ meeting to try to get the fateful German
race cancelled, on screen it is Hunt who leads the opposition, giving the
impression that Lauda is attempting to rig the championship.

It is never mentioned that the rivals were friendly enough to share a flat as
young men; there is a famous photograph of them chatting that reveals levels
of kinship that the film only belatedly hints at.

It makes for a great story, as told on screen, but it is not absolutely
accurate.

Morgan says he was very conscious of the responsibility of this. “At the end
of the film, I don’t think you leave the cinema in any doubt whatsoever
about the affection and respect between the two men,” he told me.

“I nudged it by no more than 10 per cent but if I over-egged the drivers’
meeting, for example, I under-egged a lot of other things, such as James’s
sexual behaviour and his use of narcotics and alcohol. My conscience is
completely clear.”

In fact, Morgan has readdressed the balance in some instances. It is true that
when Lauda returned to racing, his face terribly scarred, a photographer
made a joke about his wife not wanting to look at him. It is not true that
Hunt beat the photographer up.

This mixing of fact and fiction is inevitable in films such as this. As Ron
Howard said: “It is not a documentary, it is interpretative.”

But it does matter. By chance, we meet at the weekend that Sir David Frost has
died, and every single appreciation makes great play of his interview with
President Nixon.

Yet, as Morgan reminds me, that interview only achieved its current level of
fame when he used it as the basis for Frost/Nixon.

“When I started researching those interviews were not in any part of the
Watergate canon,” he said.

“And I am both delighted to have brought them to people’s attention and also
feel very responsible for the fact that I am writing this kind of stuff.”

Howard concluded our meeting with an anecdote about a man who utterly hated
his film Apollo 13, also based on a true story, about the battle to
save the three astronauts on the doomed space shuttle.

“It’s the ending. It is so Hollywood. Those guys would never have survived,”
he replied.

Which all goes to show that the relationship between truth and fiction is
never simple.

Rush is released on Sept 14