If there’s one phrase guaranteed to chill a movie studio executive to the marrow, it has to be “passion project.” Because for every one of those that pays off at the box office, the disasters are the ones we remember.

Steve McQueen was the biggest box office star in the world in the late 1960s. “Bullitt” and “The Thomas Crown Affair” secured that. And what did he want to spend all that Hollywood capital on? A movie about sports car racing, his biggest passion at the time.

His production company got financing, he hired his “Great Escape/Magnificent Seven” director, John Sturges, recruited a cadre of drivers and rounded up cars and went to LeMans to film the 1970 24 Hours of LeMans race. But they went without a script.

The resulting movie was a glorious, documentary-like muddle, and not the final word on racing films, or even the best racing movie of the era. James Garner and John Frankenheimer’s “Grand Prix” was better. And McQueen was never the same after the debacle — his power in Hollywood diminished, his fervor for the sport nearly gone.

“Steve McQueen: The Man & LeMans,” revisits the project and the iconic star behind it, and makes for a revealing and thoroughly entertaining peek into Hollywood history. Using audio taped interviews, including some from the last months of McQueen’s life — he died of cancer in 1980 — archival interviews and fresh conversations with those who were there, as well as “lost” footage from the one million feet of film McQueen & Co. shot at LeMans, veteran car-racing filmmakers Gabriel Clarke and John McKenna dissect a fascinating failure that stands tall, decades later, as a moment captured in time.

“I just wanted to get it down on film,” McQueen said at the time, “what I thought it was all about.”

So he and his SOLAR Productions set up camp and started filming. They came up with all sorts of camera rigs to capture filming, no mean feat two generations before tiny ProCams and GoPros made shots inside, beside and all around the car routine.

“Grand Prix,” about Formula 1 racing, got to some of these innovations first, as well. And don’t think McQueen didn’t realize this. One and all relate how jealous and resentful he was that Garner & Co, made their racing movie and got it into theaters ahead of him.

We hear about the dangers of the sport back then from the drivers — Jonathan Williams and David Piper among them.

And we get a taste of who the “King of Cool” was and is, the Missouri boy who became the biggest film star of his day. The actor did a lot of his own motorcycle and car driving stunts, took crazy risks on tracks in between movies, drove a Porsche with a broken clutch-foot to a second place finish at Sebring, and lived on guts and adrenaline.

His favorite screenwriter, Alan Trustman, talks about where McQueen was, post “Thomas Crown” and “Bullitt,” and of his efforts to “save” “LeMans” by concocting a script to fit around all that marvelous footage they were getting.

McQueen wasn’t having it. Eventually, Sturges, the director, quit. McQueen bullied the studio-imposed replacement, womanized at will, crashed a car after hours with a starlet and possible conquest on board (Louise Edlind is a little vague on that).

McQueen’s widow, Neile, talks about that, and the marriage that finally unraveled during the filming. McQueen took up with Ali MacGraw while making “The Getaway,” his next film.

And McQueen’s adoring son Chad dominates the film as the former kid who remembers, in vivid detail, much of what happened back then — wrecks, racecar rides, the works. He and others marvel at what the film really cost his father. Insurance issues meant McQueen couldn’t actually race at LeMans while making the movie. He lost his one chance at the pinnacle of his sport making this movie.

The film? I’ve seen it recently, and it’s still more striking to look at than engrossing to sit through. But “The Man & LeMans” is a great documentary for explaining his ambitions and passions, and all the trouble the arrogance of Hollywood power can get you into.

LIMITED RELEASE: Nov. 13, VOD and DVD, Dec. 1

MPAA Rating: unrated, profanity

Cast: Steve McQueen, Chad McQueen, Siegfried Rauch, Neile Adams McQueen, Louise Edlind, John Sturges, David Piper
Credits: Directed by Gabriel Clarke and John McKenna. A FilmRise release.

Running time: 1:42